Single-nephron adaptations to partial renal ablation in cats

1995 ◽  
Vol 269 (5) ◽  
pp. R1002-R1008 ◽  
Author(s):  
S. A. Brown ◽  
C. A. Brown
Keyword(s):  
Mesangial Matrix ◽  
Morphological Studies ◽  
Sham Surgery ◽  
Effective Filtration Pressure ◽  
Renal Ablation ◽  
Matrix Expansion ◽  
Single Nephron ◽  
The Mean ◽  
Group 2 ◽  
Group 1

To evaluate remnant nephron hyperfiltration, cats underwent sham surgery (group 1, n = 6) or three-fourths nephrectomy (group 2, n = 6). Four to six weeks later, micropuncture studies demonstrated increases (P < 0.01) of single-nephron glomerular filtration rate (SNGFR) in group 2 (28.1 +/- 2.8 vs. 56.0 +/- 5.9 nl/min). In group 2 the mean estimated glomerular capillary pressure of 74.0 +/- 1.7 mmHg exceeded (P < 0.01) the value for group 1 (62.6 +/- 1.4 mmHg). The mean effective filtration pressure (EFPm) for group 2 (28.7 +/- 3.1 mmHg) was greater (P < 0.05) than that in group 1 (20.8 +/- 1.9 mmHg). Similarly, the mean ultrafiltration coefficient (Kf) in group 2 of 2.03 +/- 0.24 nl.min-1.mmHg-1 exceeded (P < 0.05) the corresponding value for group 1 of 1.35 +/- 0.06 nl.min-1.mmHg-1. Morphological studies demonstrated glomerular enlargement and mesangial matrix expansion in group 2 (P < 0.05). Proteinuria, as assessed by the urine protein-to-creatinine ratio, was increased (P < 0.05) after partial renal ablation. These results demonstrate that increases in SNGFR in feline remnant nephrons occur in association with glomerular hypertension, glomerular hypertrophy, expansion of mesangial matrix, and proteinuria, and furthermore, that the observed increases in SNGFR are attributable to an augmentation of EFPm and Kf.

Single-nephron adaptations to partial renal ablation in the dog

1990 ◽  
Vol 258 (3) ◽  
pp. F495-F503 ◽  
Author(s):  
S. A. Brown ◽  
D. R. Finco ◽  
W. A. Crowell ◽  
D. C. Choat ◽  
L. G. Navar
Keyword(s):  
Mean Value ◽  
Hydraulic Pressure ◽  
Renal Ablation ◽  
Single Nephron ◽  
Group 3 ◽  
Flow Pressure ◽  
The Mean ◽  
Group 2 ◽  
Stop Flow ◽  
Group 1

Micropuncture and histological studies were performed in dogs to characterize single-nephron adaptations to partial renal ablation. Dogs underwent sham surgery (group 1, n = 6), three-fourths nephrectomy (group 2, n = 10), or seven-eighths nephrectomy (group 3, n = 6). Single-nephron glomerular filtration rate (SNGFR) was 71.0 +/- 4.2 nl/min in group 1, 132.5 +/- 9.6 nl/min in group 2, and 161.8 +/- 12.4 nl/min in group 3 (P less than 0.05). There were parallel increases in single-nephron glomerular plasma flow rate (GPF), with a mean value of 235.3 +/- 20.1 nl/min in group 1, 442.4 +/- 34.4 nl/min in group 2, and 569.6 +/- 73.7 nl/min in group 3 (P less than 0.05, group 1 vs. groups 2 and 3). Glomerular capillary pressure, estimated from the sum of proximal tubule stop-flow pressure and arterial oncotic pressure, was 63.2 +/- 1.9 mmHg in group 1, 73.5 +/- 2.0 mmHg in group 2, and 77.9 +/- 2.2 mmHg in group 3 (P less than 0.05, group 1 vs. groups 2 and 3). The mean glomerular transcapillary hydraulic pressure gradient (delta P) in group 2 was not different from group 1 (46.8 +/- 1.3 vs. 43.9 +/- 1.8 mmHg, NS); however, it was significantly increased in group 3 (50.0 +/- 1.4 mmHg; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Increased single-nephron protein excretion after renal ablation in nephrotic rats

1988 ◽  
Vol 255 (6) ◽  
pp. F1243-F1248 ◽  
Author(s):  
T. W. Meyer ◽  
H. G. Rennke
Keyword(s):  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Hydraulic Pressure ◽  
Nephron Number ◽  
Renal Ablation ◽  
Single Nephron ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

The effects of reducing nephron number in rats with established nephrosis were investigated. Rats received an injection of adriamycin and were divided into three groups with similar values for proteinuria after 4 wk. Group 1 rats were then subjected to sham operation. Group 2 rats were subjected to four-fifths renal ablation, and group 3 rats were subjected to four-fifths renal ablation and then maintained on enalapril. Micropuncture and morphological studies were performed 3 wk later. During this 3-wk period, proteinuria increased slightly in each group. Increased proteinuria in groups 2 and 3 reflected a dramatic increase in remnant nephron proteinuria after renal ablation in nephrotic rats. Increased remnant nephron proteinuria in groups 2 and 3 was associated with increased single-nephron glomerular filtration rate (group 1, 30 +/- 2 nl/min; group 2, 54 +/- 3 nl/min; group 3, 41 +/- 4 nl/min) and increased glomerular volume (group 1, 0.93 +/- 0.05 x 10(6) micron 3; group 2, 1.30 +/- 0.09 x 10(6) micron 3; group 3, 1.27 +/- 0.05 x 10(6) micron 3). The increase in single-nephron glomerular filtration rate after renal ablation in both group 2 and 3 rats was attributable to an increase in glomerular plasma flow (group 1, 119 +/- 14 nl/min; group 2, 217 +/- 18 nl/min; group 3, 183 +/- 13 nl/min) without a significant increase in glomerular transcapillary hydraulic pressure (group 1, 45 +/- 1 mmHg; group 2, 48 +/- 3 mmHg; group 3, 44 +/- 2 mmHg). Group 2 exhibited an increase in systemic blood pressure that was prevented by enalapril treatment in group 3. These studies show that an increase in remnant nephron proteinuria accompanies glomerular hypertrophy and hyperfiltration when nephron number is reduced in nephrotic rats. This increase in remnant nephron proteinuria is not attributable to elevation of systemic or glomerular capillary pressure.

Hypertension and progressive glomerular injury caused by focal glomerular ischemia

1990 ◽  
Vol 259 (2) ◽  
pp. F239-F245 ◽  
Author(s):  
P. L. Miller ◽  
H. G. Rennke ◽  
T. W. Meyer
Keyword(s):  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Systemic Hypertension ◽  
Glomerular Injury ◽  
Renal Embolization ◽  
Glomerular Capillary ◽  
Morphological Studies ◽  
The Mean ◽  
Group 2 ◽  
Group 1

Sprague-Dawley rats received infusions of 55-microns microspheres (groups 1 and 3) or dextrose (groups 2 and 4) into both renal arteries. Groups 1 and 2 rats were studied over 7 mo. In group 1 rats renal embolization increased the mean arterial pressure (group 1, 140 +/- 4 mmHg; group 2, 118 +/- 2 mmHg) without reducing the glomerular filtration rate (GFR; group 1, 4.69 +/- 0.16 ml/min; group 2, 4.57 +/- 0.22 ml/min). Micropuncture studies showed that systemic hypertension was accompanied by an increase in the glomerular capillary pressure of functioning nephrons in group 1 rats. Morphological studies showed that renal embolization caused both glomerular ischemia (group 1, 11.8 +/- 1.9% of glomeruli; group 2, 0.1 +/- 0.1% of glomeruli) and glomerular segmental sclerosis (group 1, 15.0 +/- 1.0% of glomeruli; group 2, 3.3 +/- 0.2% of glomeruli). Groups 3 and 4 rats were studied over 2 mo. Renal embolization again increased the mean arterial pressure without reducing the GFR in group 3 rats. Morphological studies showed that at 2 mo renal embolization caused glomerular ischemia without glomerular segmental sclerosis. These studies show that focal glomerular ischemia can cause systemic and glomerular capillary hypertension in the absence of a reduction in the GFR. They further show that focal glomerular ischemia can cause progressive sclerotic injury in the remaining, nonischemic portion of the glomerular population.

Effect of secretin on glomerular dynamics in dogs

1986 ◽  
Vol 250 (2) ◽  
pp. F256-F260 ◽  
Author(s):  
G. R. Marchand
Keyword(s):  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Plasma Flow ◽  
Filtration Rate ◽  
Renal Plasma Flow ◽  
Time Control ◽  
Effective Filtration Pressure ◽  
Single Nephron ◽  
Group 2 ◽  
Group 1

These studies were performed to determine whether a role for increased renal plasma flow (RPF) in the regulation of glomerular filtration rate (GFR) could be demonstrated in dogs by infusing the polypeptide hormone secretin, a vasodilator that has been reported to increase GFR. Differences between control and recollection periods were compared by paired t test in five time-control dogs (group 1) and 10 secretin dogs (group 2). In group 2, secretin (100 mU . kg-1 . min-1, ia) significantly increased single-nephron glomerular filtration rate (SNGFR) 11.1 +/- 3.1 nl/min (20%) and glomerular plasma flow 59 +/- 11 nl/min (26%). Similar increases in GFR (26%) and RPF (29%) were observed. Secretin also increased glomerular capillary pressure 5.2 +/- 0.8 mmHg and free-flow proximal tubule pressure 5.5 +/- 1.0 mmHg. Secretin did not significantly affect average effective filtration pressure (EFP) but significantly increased the ultrafiltration coefficient (Kf) 0.74 +/- 0.14 nl . min-1 . mmHg-1. These differences were significantly greater than those observed in group 2. It is concluded that secretin increased SNGFR primarily by an effect on Kf. This is consistent with the marked effect that Kf is predicted to have on glomerular filtration in dogs. The maintenance of EFP agrees with other vasodilator studies and indicates that GFR is only moderately dependent on plasma flow in dogs.

Creation of physiologic rhythm by closed loop stimulation in heart failure patients with severe chronotropic incompetence: worldwide first results of a pilot study

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
J Proff ◽  
B Merkely ◽  
R Papp ◽  
C Lenz ◽  
P.J Nordbeck ◽  
...  
Keyword(s):  
Heart Rate ◽  
Closed Loop ◽  
Funding Source ◽  
Chronotropic Incompetence ◽  
First Results ◽  
The Mean ◽  
Group 2 ◽  
Group 1

Abstract Background The prevalence of chronotropic incompetence (CI) in heart failure (HF) population is high and negatively impacts prognosis. In HF patients with an implanted cardiac resynchronisation therapy (CRT) device and severe CI, the effect of rate adaptive pacing on patient outcomes is unclear. Closed loop stimulation (CLS) based on cardiac impedance measurement may be an optimal method of heart rate adaptation according to metabolic need in HF patients with severe CI. Purpose This is the first study evaluating the effect of CLS on the established prognostic parameters assessed by the cardio-pulmonary exercise (CPX) testing and on quality of life (QoL) of the patients. Methods A randomised, controlled, double-blind and crossover pilot study has been performed in CRT patients with severe CI defined as the inability to achieve 70% of the age-predicted maximum heart rate (APMHR). After baseline assessment, patients were randomised to either DDD-CLS pacing (group 1) or DDD pacing at 40 bpm (group 2) for a 1-month period, followed by crossover for another month. At baseline and at 1- and 2-month follow-ups, a CPX was performed and QoL was assessed using the EQ-5D-5L questionnaire. The main endpoints were the effect of CLS on ventilatory efficiency (VE) slope (evaluated by an independent CPX expert), the responder rate defined as an improvement (decrease) of the VE slope by at least 5%, percentage of maximal predicted heart rate reserve (HRR) achieved, and QoL. Results Of the 36 patients enrolled in the study, 20 fulfilled the criterion for severe CI and entered the study follow-up (mean age 68.9±7.4 years, 70% men, LVEF=41.8±9.3%, 40%/60% NYHA class II/III). Full baseline and follow-up datasets were obtained in 17 patients. The mean VE slope and HRR at baseline were 34.4±4.4 and 49.6±23.8%, respectively, in group 1 (n=7) and 34.5±12.2 and 54.2±16.1% in group 2 (n=10). After completing the 2-month CPX, the mean difference between DDD-CLS and DDD-40 modes was −2.4±8.3 (group 1) and −1.2±3.5 (group 2) for VE slope, and 17.1±15.5% (group 1) and 8.7±18.8% (group 2) for HRR. Altogether, VE slope improved by −1.8±2.95 (p=0.31) in DDD-CLS versus DDD-40, and HRR improved by 12.9±8.8% (p=0.01). The VE slope decreased by ≥5% in 47% of patients (“responders to CLS”). The mean difference in the QoL between DDD-CLS and DDD-40 was 0.16±0.25 in group 1 and −0.01±0.05 in group 2, resulting in an overall increase by 0.08±0.08 in the DDD-CLS mode (p=0.13). Conclusion First results of the evaluation of the effectiveness of CLS in CRT patients with severe CI revealed that CLS generated an overall positive effect on well-established surrogate parameters for prognosis. About one half of the patients showed CLS response in terms of improved VE slope. In addition, CLS improved quality of life. Further clinical research is needed to identify predictors that can increase the responder rate and to confirm improvement in clinical outcomes. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Biotronik SE & Co. KG

Comparison of the ATRIA, CHA2DS2-VASc, and Modified Scores ATRIA-HSV, CHA2DS2-VASc-HS, for the Prediction of Coronary Artery Disease Severity

Angiology ◽  
2021 ◽  
pp. 000331972199141
Author(s):  
Arafat Yildirim ◽  
Mehmet Kucukosmanoglu ◽  
Fethi Yavuz ◽  
Nermin Yildiz Koyunsever ◽  
Yusuf Cekici ◽  
...  
Keyword(s):  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Vascular Disease ◽  
Operating Characteristics ◽  
Coronary Artery Disease Severity ◽  
Group 3 ◽  
The Mean ◽  
Group 2 ◽  
Artery Disease ◽  
Group 1

Many parameters included in the Anticoagulation and Risk Factors in Atrial Fibrillation (ATRIA) and CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke, vascular disease, age 65-74 years, sex category) scores also predict coronary artery disease (CAD). We modified the ATRIA score (ATRIA-HSV) by adding hyperlipidemia, smoking, and vascular disease and also male sex instead of female. We evaluated whether the CHA2DS2-VASc, CHA2DS2-VASc-HS, ATRIA, and ATRIA-HSV scores predict severe CAD. Consecutive patients with coronary angiography were prospectively included. A ≥50% stenosis in ≥1epicardial coronary artery (CA) was defined as severe CAD. Patient with normal CA (n = 210) were defined as group 1, with <50% CA stenosis (n = 178) as group 2, and with ≥50% stenosis (n = 297) as group 3. The mean ATRIA, ATRIA-HSV, CHA2DS2-VASc, and CHA2DS2VASc-HS scores increased from group 1 to group 3. A correlation was found between the Synergy between PCI with Taxus and Cardiac Surgery score and ATRIA ( r = 0.570), ATRIA-HSV ( r = 0.614), CHA2DS2-VASc ( r = 0.428), and CHA2DS2-VASc-HS ( r = 0.500) scores ( Ps < .005). Pairwise comparisons of receiver operating characteristics curves showed that ATRIA-HSV (>3 area under curve [AUC]: 0.874) and ATRIA (>3, AUC: 0.854) have a better performance than CHA2DS2-VASc (>1, AUC: 0.746) and CHA2DS2-VASc-HS (>2, AUC: 0.769). In conclusion, the ATRIA and ATRIA-HSV scores are simple and may be useful to predict severe CAD.

Does Presurgical Nasoalveolar Molding Have a Long-Term Effect on Nasal and Upper Airway Dimensions?

2020 ◽  
pp. 105566562098023
Author(s):  
Ashwina S. Banari ◽  
Sanjeev Datana ◽  
Shiv Shankar Agarwal ◽  
Sujit Kumar Bhandari
Keyword(s):  
Upper Airway ◽  
P Value ◽  
Airway Patency ◽  
The Mean ◽  
Group 2 ◽  
Acoustic Pharyngometry ◽  
Nasoalveolar Molding ◽  
Area And Volume ◽  
Group 1

Objectives: To compare nasal and upper airway dimensions in patients with cleft lip and palate (CLP) who underwent nasoalveolar molding (NAM) with those without NAM during infancy using acoustic pharyngometry and rhinometry. Materials and Methods: Eccovision acoustic pharyngometry and rhinometry (Sleep Group Solutions) was used for assessment of mean area and volume of nasal and upper airway in patients with complete unilateral CLP (age range 16-21 years) treated with NAM (group 1, n = 19) versus without NAM (group 2, n = 22). Results: The mean nasal cross-sectional areas and volume were higher in group 1 compared to group 2 on both cleft ( P value <.001) and noncleft side ( P value >.05). The mean area and volume of upper airway were also significantly higher in group 1 compared to group 2 ( P value <.05). Conclusions: Nasoalveolar molding being one of the first interventions in chronology of treatment of patients with CLP, its long-term outcome on nasal and upper airway patency needs to be ascertained. The results of the present study show that the patients with CLP who have undergone NAM during infancy have better improvement in nasal and upper airway patency compared with those who had not undergone NAM procedure. The basic advantages of being noninvasive, nonionizing and providing dynamic assessment of nasal and upper airway patency make acoustic pharyngometry and rhinometry a diagnostic tool of choice to be used in patients with CLP.

scholarly journals Comparison of Bite Force in Patients After Treatment of Mandibular Fractures With 3-Dimensional Locking Miniplate and Standard Miniplates

2019 ◽  
Vol 1 (1) ◽  
pp. 7-10
Author(s):  
Gaurav Singh ◽  
Madan Mishra ◽  
Amit Gaur ◽  
Dhritiman Pathak
Keyword(s):  
Treatment Strategies ◽  
Bite Force ◽  
Mandibular Fractures ◽  
Time Intervals ◽  
Experimental Conditions ◽  
3 Dimensional ◽  
The Mean ◽  
Group 2 ◽  
Drilling Conditions ◽  
Group 1

Background: Fractures of the mandible can be studied and described in anatomic terms, functional considerations, treatment strategies, and outcome measures. The performance of any fixation system depends on multiple factors including plate adaptation, screw placement, bone quality, drilling conditions, and postoperative patient compliance. Bite force assesses masticatory muscle function under clinical and experimental conditions. Method: 30 patients with isolated, noncomminuted mandibular fractures were randomly divided into two equal groups. Group 1 patients were treated using 3-dimensional locking miniplates and group 2 patients were treated with standard miniplates. The bite forces were recorded at definite time intervals: preoperatively, and second week, sixth week, third month, and sixth month postoperatively. Result: At 6 weeks postoperative, 3 month postoperative, and 6 month postoperative, the mean bite force was found to be significantly higher among group 1 patients as compared to those in group 2 in all the sites. While at 2 week postoperative, the mean bite force was found to be significantly higher in Group 2 as compared to Group 1 at incisor region. Conclusion: The overall results of the present study show better performance in bite force for the 3-dimensional locking miniplate when compared with standard miniplates.

scholarly journals Repair Integrity and Functional Outcomes Between Knot-Tying and Knotless Suture-Bridge Arthroscopic Rotator Cuff Repair: A Prospective Randomized Clinical Trial

2021 ◽  
Vol 9 (4) ◽  
pp. 232596712110024
Author(s):  
Koray Şahin ◽  
Fatih Şentürk ◽  
Mehmet Ersin ◽  
Ufuk Arzu ◽  
Mechmet Chodza ◽  
...  
Keyword(s):  
Rotator Cuff ◽  
Constant Score ◽  
Knot Tying ◽  
Suture Bridge ◽  
Significant Difference ◽  
The Mean ◽  
Group 2 ◽  
Cuff Repair ◽  
Group 1

Background: Knot-tying suture-bridge (SB) rotator cuff repair may compromise the vascularity of the repaired tendon, causing tendon strangulation and medial repair failure. The knotless SB repair technique has been proposed to overcome this possibility and decrease retear rates. Purpose: To compare clinical and structural outcomes and retear patterns between the knot-tying and knotless SB techniques. We hypothesized that the knotless technique would result in lower retear rates owing to the preservation of intratendinous vascularity. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 104 patients with full-thickness rotator cuff tears were randomly and prospectively allocated to undergo knot-tying (group 1) or knotless (group 2) SB repair. Clinical outcome measures included range of motion, the visual analog scale (VAS) for pain, and the Constant score for function. Repair integrity was evaluated on magnetic resonance imaging scans using the Sugaya classification. Retears were also classified according to their pattern as type 1 (lateral) or type 2 (medial). Results: Overall, 88 patients (group 1: n = 42 [mean ± SD age, 54.3 ± 9.8 years]; group 2: n = 46 [mean ± SD age, 55.8 ± 8.2 years]) were included in the final analysis. The mean ± SD follow-up period was 25.4 ± 8.3 and 23.3 ± 7.2 months for groups 1 and 2, respectively. From preoperatively to postoperatively, the mean VAS pain score improved significantly in both groups (group 1: from 7.4 ± 1.7 to 1.0 ± 1.7; group 2: from 7.1 ± 1.9 to 1.3 ± 2.0; P < .0001 for both), as did the mean ± SD Constant score (group 1: from 51.7 ± 13.4 to 86.0 ± 11.5; group 2: from 49.4 ± 18.4 to 87.2 ± 14.8; P < .0001 for both). There was no significant difference between the groups for the postoperative VAS or Constant score. The retear rate was not significantly different between the groups (19.0% [8/42] in group 1 and 28.3% [13/46] in group 2; P > .05). There was a significant difference in the type 2 failure rate (75.0% [6/8] in group 1 and 23.1% [3/13] in group 2; P = .03). Conclusion: Both techniques showed excellent improvement and comparable clinical outcomes, and there was no significant difference in retear rates. Consistent with previously published data, the type 2 failure rate was significantly higher with the knot-tying technique. Registration: NCT03982108 ( ClinicalTrials.gov identifier).

TO ASSESS THE IDEAL TIME OF LAPAROSCOPIC CHOLECYSTECTOMY AFTER ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY IN CASES OF CHOLELITHIASIS WITH CHOLEDOCHOLITHIASIS

2021 ◽  
Vol 5 (4) ◽  
Author(s):  
Dhirendra Godara ◽  
Vineet Choudhary ◽  
Nitish Soni
Keyword(s):  
Laparoscopic Cholecystectomy ◽  
Endoscopic Retrograde Cholangiopancreatography ◽  
Medical Sciences ◽  
Early Recovery ◽  
Endoscopic Retrograde ◽  
The Mean ◽  
Group 2 ◽  
Late Group ◽  
Group 1 ◽  
The Ideal

Background: Aims of this study was assess the ideal time of laparoscopic cholecystectomy after endoscopic retrograde cholangiopancreatography in cases of cholelithiasis with Choledocholthiasis Methods: The present study was carried out on 150 patients admitted in Department of General surgery National Institute of Medical Sciences and Research, Jaipur, diagnosed with cholelithiasis along with choledocholithiasis  from 1stJanuary 2019 to 30thJune, 2020. Results: In group 1 out of 75 patients 7 patients developed complications in post operative period compared to 35 patients out of 75 patients developed complications in group 2. The The mean hospital stay (in day) in group 1 patients was 2.26, median 2 and the mean of group 2 was 5.26, median 5. Conclusion: To conclude in our study there has been found significant advantage of early laparoscopic cholecystecomy following ERCP over the late group to minimize complications and promote early recovery of the patients. Keywords: ERCP, Cholecystectomy, Endoscopic retrograde cholangiopancreatography

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