Wall Mechanics of the Stented Rabbit Aorta: Long-Term Study and Correlation with Histological Findings

2003 ◽  
Vol 10 (3) ◽  
pp. 577-584 ◽  
Author(s):  
Hélène Vernhet ◽  
Roland Demaria ◽  
Antonia Pérez-Martin ◽  
Jean Marie Juan ◽  
Marie Claire Oliva-Lauraire ◽  
...  
Keyword(s):  
Rabbit Aorta ◽  
Intimal Thickening ◽  
Injury Score ◽  
Stent Deployment ◽  
Long Term Study ◽  
Stent Expansion ◽  
Significant Difference ◽  
Group A ◽  
Group B

Purpose: To evaluate long-term changes in arterial wall mechanics induced by stenting of the rabbit aorta. Methods: Eighteen New Zealand white rabbits had initial stent deployment (3×8 mm Multilink) at 110% of the pre-stenting abdominal aortic diameter. Group A (n=10) had no post-deployment stent expansion and group B (n=8) had 30% overdilation of the stent. A noninvasive B-mode ultrasound examination coupled with image processing allowed measurement of diameters at systole and diastole and the calculation of diameter compliance. Measurements were performed before stenting and compared to those recorded immediately after stenting and at 3 months at 3 locations: upstream from the stent, at the stent level, and downstream from the stent. Measurements were also compared among measurement sites. The pathological study included measurement of intimal thickening and calculation of an injury score. Results: At the stent level, diameter compliance was significantly lower after initial stenting and at 3 months than before stenting (group A: p<0.005; group B: p<0.001) and than downstream or upstream from the stent (group A: p<0.0001, group B: p<0.005). No significant difference in diameter compliance was found between groups A and B. In group B, intimal thickening and the injury score were greater than in group A (p<0.05 and p<0.0001, respectively). Conclusions: Endovascular stenting of the rabbit aorta impairs wall mechanics. Performing 30% overdilation of the stent does not worsen this impairment but induces greater in-stent intimal hyperplasia.

Management of fresh odontoid fractures using posterior C1–2 fixation without fusion: a long-term clinical follow-up study

2021 ◽  
pp. 1-11
Keyword(s):  
Scale Score ◽  
Neck Disability Index ◽  
Implant Removal ◽  
Odontoid Fractures ◽  
Significant Difference ◽  
Flexion Extension ◽  
Group A ◽  
Group B

OBJECTIVE Posterior C1–2 fixation without fusion makes it possible to restore atlantoaxial motion after removing the implant, and it has been used as an alternative technique for odontoid fractures; however, the long-term efficacy of this technique remains uncertain. The purpose of the present study was to explore the long-term follow-up outcomes of patients with odontoid fractures who underwent posterior C1–2 fixation without fusion. METHODS A retrospective study was performed on 62 patients with type II/III fresh odontoid fractures who underwent posterior C1–2 fixation without fusion and were followed up for more than 5 years. The patients were divided into group A (23 patients with implant removal) and group B (39 patients without implant removal) based on whether they underwent a second surgery to remove the implant. The clinical outcomes were recorded and compared between the two groups. In group A, the range of motion (ROM) of C1–2 was calculated, and correlation analysis was performed to explore the factors that influence the ROM of C1–2. RESULTS A solid fracture fusion was found in all patients. At the final follow-up, no significant difference was found in visual analog scale score or American Spinal Injury Association Impairment Scale score between the two groups (p > 0.05), but patients in group A had a lower Neck Disability Index score and milder neck stiffness than did patients in group B (p < 0.05). In group A, 87.0% (20/23) of the patients had atlantoodontoid joint osteoarthritis at the final follow-up. In group A, the C1–2 ROM in rotation was 6.1° ± 4.5° at the final follow-up, whereas the C1–2 ROM in flexion-extension was 1.8° ± 1.2°. A negative correlation was found between the C1–2 ROM in rotation and the severity of tissue injury in the atlantoaxial region (r = –0.403, p = 0.024) and the degeneration of the atlantoodontoid joint (r = –0.586, p = 0.001). CONCLUSIONS Posterior C1–2 fixation without fusion can be used effectively for the management of fresh odontoid fractures. The removal of the implant can further improve the clinical efficacy, but satisfactory atlantoaxial motion cannot be maintained for a long time after implant removal. A surgeon should reconsider the contribution of posterior C1–2 fixation without fusion and secondary implant removal in preserving atlantoaxial mobility for patients with fresh odontoid fractures.

scholarly journals The Impact of Visual Aids on the Retention of English Word Stress Patterns

2018 ◽  
Vol 7 (2) ◽  
pp. 225 ◽  
Author(s):  
Farid Ghaemi ◽  
Fahimeh Rafi
Keyword(s):  
English Word ◽  
Placement Test ◽  
Visual Aids ◽  
Word Stress ◽  
Significant Difference ◽  
Group A ◽  
Group B ◽  
The Impact ◽  
Stress Patterns

The present study aimed at comparing the effectiveness of three different techniques on learners’ long term memorization of English word stress patterns. After administering a quick placement test, 67 Iranian EFL elementary learners at language institutes were selected to participate in the study. Then they were divided into three groups. Before starting the instruction, a pretest was conducted to classify the participants’ abilities on word stress patterns. Then the new techniques were used to teach English word stress patterns. In all three groups, words were printed largely on a piece of paper and the syllables were clearly specified by dots. In group ‘A’, pronunciation and stress pattern of new words were taught aurally through the repetition of the words. In group ‘B’, all the procedure was exactly similar to that of group ‘A’, the only difference was that the stressed syllables were printed in bold. In group ‘C’, all the procedure was exactly similar to that of group ‘B’,  except that the stressed syllables were not only printed in bold, but also introduced by teacher’s hand gesture. After two weeks, a delayed posttest was conducted to check long term memorization of the word stress patterns. The results of the study indicated that there was a significant difference between pretest and delayed posttest in all three groups. But the most meaningful difference belonged to group ‘C’. That is, the participants in the third group (gesture group) outperformed those in the other groups. Finally, some implications and suggestions provided for further research.   

scholarly journals Assessment of Range of Movement, Pain and Disability Following a Whiplash Injury

2017 ◽  
Vol 11 (1) ◽  
pp. 541-545 ◽  
Author(s):  
Atif A. Malik ◽  
Simon Robinson ◽  
Wasim S. Khan ◽  
Bernice Dillon ◽  
Martyn E. Lovell
Keyword(s):  
Neck Pain ◽  
Whiplash Injury ◽  
Range Of Movement ◽  
Pain Group ◽  
Pain Scores ◽  
Significant Difference ◽  
Group A ◽  
Group B ◽  
Group D

Background: Whiplash has been suggested to cause chronic symptoms and long term disability. This study was designed to assess long term function after whiplash injury. Material & Methods: A random sample of patients in the outpatient clinic was interviewed, questionnaire completed and clinical examination performed. Assessment was made of passive cervical range of movement and Visual Analogue Scale pain scores. One hundred and sixty-four patients were divided into four different groups including patients with no whiplash injury but long-standing neck pain (Group A), previous symptomatic whiplash injury and long-standing neck pain (Group B), previous symptomatic whiplash injury and no neck symptoms (Group C), and a control group of patients with no history of whiplash injury or neck symptoms (Group D). Results: Data was analyzed by performing an Independent samples t-test and ANOVA, with level of significance taken as p<0.05. Comparing the four groups using a one-way ANOVA showed a significant difference between the groups (p<0.001). There were significant differences when comparing mean ranges of movement between Group A and Group D, and between Group B and Group D. There was no significant difference between Group C and Group D. similar differences were also seen in the pain scores. Conclusion: We conclude that osteoarthritis in the cervical spine, and whiplash injury with chronic problems cause a significantly decreased cervical range of movement with a higher pain score. Patients with shorter duration of whiplash symptoms appear to do better in the long-term.

scholarly journals Intravenous and subsequent long-term oral tranexamic acid in enhanced-recovery primary total knee arthroplasty without the application of a tourniquet: a randomized placebo-controlled trial

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Hao-Yang Wang ◽  
Liu Wang ◽  
Ze-Yu Luo ◽  
Duan Wang ◽  
Xin Tang ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Blood Loss ◽  
Tranexamic Acid ◽  
Knee Arthroplasty ◽  
Total Blood ◽  
Significant Difference ◽  
Group A ◽  
Total Knee ◽  
Group B

Abstract Background To assess the efficacy and safety of intravenous and subsequent long-term oral tranexamic acid (TXA) following total knee arthroplasty (TKA) without a tourniquet. Methods In this double-blinded trial, 118 patients undergoing primary TKA were randomized into two groups: the patients in group A received intravenous TXA at 20-mg/kg 10 min before the surgery and 3 h postoperatively, and then oral 1 g TXA from postoperative day (POD) 1 to POD 14, and the patients in group B received intravenous TXA at 20-mg/kg 10 min before surgery and 3 h postoperatively, and then oral 1 g placebo from postoperative day (POD) 1 to POD 14. The primary outcome was total blood loss. Secondary outcomes included ecchymosis area and morbidity, postoperative transfusion, postoperative laboratory values, postoperative knee function and length of hospital stay. Complications, and patient satisfaction were also recorded. Results The mean total blood loss was lower in Group A than in Group B (671.7 ml vs 915.8 ml, P = 0.001). There was no significant difference in the transfusion rate between the two groups. Group A had a higher hemoglobin than Group B on POD 3 (106.0 g/L vs 99.7 g/L, P = 0.001). However, no significant difference was found for Hb or hematocrit on POD 1 or POD 14 between the two groups. Patients in Group A had less ecchymosis morbidity (7 vs 38, P = 0.001), smaller ecchymosis area (1.6 vs 3.0, P = 0.001) than Group B. The blood coagulation level as measured by fibrinolysis (D-Dimer) was lower in Group A than in Group B on POD 1 and POD 3 (4.6 mg/L vs. 8.4 mg/L, respectively, P = 0.001; 1.5 mg/L vs. 3.3 mg/L, respectively, P = 0.001). However, there was no significant difference on POD 14, and the fibrin degradation products showed the same trend. Patients in Group A had less swelling than those in Group B on POD 3 and POD 14. The circumference of the knee was 43.1 cm vs. 46.1 cm (POD 3, P = 0.001) and 41.4 cm vs. 44.9 cm (POD 14, P = 0.001) in Group A vs Group B, respectively. Nevertheless, the circumference of the knee in the two groups was similar on POD 1 and POD 3 M. No significant differences were identified in knee function, pain score, or hospital stay. No significant differences were identified in thromboembolic complications, infection, hematoma, wound healing and patients satisfaction between the two groups. Conclusion Intravenous and subsequent long-term oral TXA produced less blood loss and less swelling and ecchymosis compared with short-term TXA without increasing the risk of complications. Trial registration The trial was registered in the Chinese Clinical Trial Registry (ChiCTR-IPR-17012264).

scholarly journals A Prospective Randomized Trial to Assess the Antireflux Effect of Antireflux Mucosectomy in the Porcine Model

2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Xuan Li ◽  
Weifeng Zhang ◽  
Meihong Chen ◽  
Shuchun Wei ◽  
Xiangyang Zhao ◽  
...  
Keyword(s):  
Gastroesophageal Reflux Disease ◽  
Proton Pump Inhibitor ◽  
Porcine Model ◽  
Gastroesophageal Junction ◽  
Control Group ◽  
Potential Efficacy ◽  
Significant Difference ◽  
Group A ◽  
Group B

Background. Both long-term proton pump inhibitor use and surgical fundoplication have potential drawbacks as treatments for chronic gastroesophageal reflux disease (GERD). Our aim was to investigate the potential efficacy of antireflux mucosectomy (ARMS) in porcine and determine the optimal circumference of resection in relation to gastroesophageal junction (GEJ). Methods. Nine pigs were allocated into the following 3 groups by computerized randomization: group A: control, group B: 1/3 circumference of the esophagus, and group C: 2/3 circumference of the esophagus. We performed mucosectomy with a crescentic mucosal resection at 3 cm above the GEJ and 1 cm below the GEJ. The animals were kept on a liquid diet for 24 h prior to endoscopy. At 6 weeks, animals underwent esophagoscopy, barium radiography, gastric yield pressure (GYP), and gastric yield volume (GYV) determination. Results. The weight of swines has no significant difference, and all pigs had maintained their weight after the procedure. We both found scar formation at the GEJ in group B and C. Compared with group A and B, group C produced significantly higher GYP (24.23±3.42 mmHg, p=0.004) and significantly smaller GYV (2200.0±238.96 mL, p=0.028) after 6 weeks. Barium radiography showed that the width of the cardia was narrower (13.73±1.19 mm, p=0.032) in group C after 6-week postprocedure. Conclusion. Our study demonstrated the potential antireflux effect of ARMS. We also recommend the 2/3 circumference resection of mucosa at 3 cm distance from the GEJ.

Arterial Stenting and Overdilation: Does it Change Wall Mechanics in Small-Caliber Arteries?

2002 ◽  
Vol 9 (6) ◽  
pp. 855-862 ◽  
Author(s):  
Hélène Vernhet ◽  
Roland Demaria ◽  
Jean-Marie Juan ◽  
Marie-Claire Oliva-Lauraire ◽  
Jean-Paul Senac ◽  
...  
Keyword(s):  
Arterial Wall ◽  
Rabbit Aorta ◽  
Infrarenal Aorta ◽  
Stent Deployment ◽  
New Zealand White Rabbits ◽  
Group A ◽  
Arterial Wall Mechanics ◽  
Wall Compliance ◽  
Group B ◽  
Arterial Stenting

Purpose: To evaluate changes in arterial wall mechanics induced by stent overdilation in the rabbit aorta. Methods: Twenty New Zealand white rabbits had initial stent deployment (3-mm × 8-mm Multilink) at 10% overdilation. Group A (n=11) had no subsequent balloon expansion of the stent and Group B (n=9) had 30% overdilation of the stent. A noninvasive B-mode ultrasound examination coupled with image processing allowed the measurement of systolic and diastolic diameter and the calculation of diameter compliance (Cd) and distensibility coefficient (DC) as indexes of arterial wall biomechanics. Measurements were performed before stenting in the infrarenal aorta, after initial stenting, and after stent overdilation at 3 locations: upstream, at the stent level, and downstream from the stent. Results: Cd was significantly lower in the stented aorta after initial stenting (p<0.0001) and after stent overdilation (p<0.0001) than before stenting. At the stent level, Cd and DC were significantly lower than downstream (p<0.0001) or upstream (p<0.0001) from the stent after initial stenting, as well as after stent overdilation. Downstream from the stent, Cd and DC were significantly lower after stent overdilation than before stenting (p<0.05). Conclusions: Endovascular stenting of the rabbit aorta produces a significant decrease in arterial wall compliance and distensibility. Stent overdilation is responsible for a slight additional decrease of compliance downstream from the stent.

Comparison of the long-term outcome of cemented Charnley low-friction arthroplasty with hybrid arthroplasty in patients with congenital hip disease

2019 ◽  
Vol 101-B (9) ◽  
pp. 1050-1057
Author(s):  
Kalliopi Lampropoulou-Adamidou ◽  
George Hartofilakidis
Keyword(s):  
Operating Time ◽  
Long Term Results ◽  
Low Friction ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Significant Difference ◽  
Hip Disease ◽  
Group A ◽  
Group B

Aims To our knowledge, no study has compared the long-term results of cemented and hybrid total hip arthroplasty (THA) in patients with osteoarthritis (OA) secondary to congenital hip disease (CHD). This is a demanding procedure that may require special techniques and implants. Our aim was to compare the long-term outcome of cemented low-friction arthroplasty (LFA) and hybrid THA performed by one surgeon. Patients and Methods Between January 1989 and December 1997, 58 hips (44 patients; one man, 43 woman; mean age 56.6 years (25 to 77)) with OA secondary to CHD were treated with a cemented Charnley LFA (group A), and 55 hips (39 patients; two men, 37 women; mean age 49.1 years (27 to 70)) were treated with a hybrid THA (group B), by the senior author (GH). The clinical outcome and survivorship were compared. Results At all timepoints, group A hips had slightly better survivorship than those in group B without a statistically significant difference, except for the 24-year survival of acetabular components with revision for aseptic loosening as the endpoint, which was slightly worse. The survivorship was only significantly better in group A compared with group B when considering reoperation for any indication as the endpoint, 15 years postoperatively (74% vs 52%, p = 0.018). Conclusion We concluded that there was not a substantial difference at almost any time in the outcome of cemented Charnley LFAs compared with hybrid THAs when treating patients with OA of the hip secondary to CHD. We believe, however, that after improvements in the design of components used in hybrid THA, this could be the method of choice, as it is technically easier with a shorter operating time. Cite this article: Bone Joint J 2019;101-B:1050–1057.

scholarly journals Persistent abnormal muscle response after microvascular decompression for hemifacial spasm

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Li Xu ◽  
Wu Xu ◽  
Jing Wang ◽  
Yulong Chong ◽  
Weibang Liang ◽  
...  
Keyword(s):  
Hemifacial Spasm ◽  
Microvascular Decompression ◽  
Duration Of Symptoms ◽  
Long Term Outcome ◽  
Muscle Response ◽  
Abnormal Muscle Response ◽  
Significant Difference ◽  
Group A ◽  
Group B

Abstract To explore the causes of persistent abnormal muscle response (AMR) after microvascular decompression (MVD) for hemifacial spasm (HFS) and the clinical outcomes of these patients. MVDs performed in Nanjing Drum Tower Hospital in 2017 were retrospectively studied, and 326 patients with HFS were classified into two groups based on whether AMR disappeared or persisted following MVD. The clinical features, treatment efficacy and postoperative complications were compared between the two groups. 305 patients with disappeared AMR after decompression were classified as Group A. In Group B, the 21 patients exhibited persistent AMR after successful MVD. The preoperative duration of symptoms in Group B was significantly longer than that in Group A (P < 0.001), and no significant difference was identified between the two groups in terms of gender, side, age and offending vessels (P > 0.05). The immediate postoperative cure rate of Group A (88.9%)was significantly higher than that in Group B (28.6%, P < 0.001), furthermore, the two groups were not different in the long-term outcome and the incidence of surgical complications (P > 0.05). The long preoperative duration of HFS patients may account for persistent AMR after successful decompression, and it is more likely for these patients to get delayed cured, the long-term outcomes showed no difference compared to those in patients with disappeared AMR after MVD.

scholarly journals The Effect of Apigenin on Pharmacokinetics of Imatinib and Its Metabolite N-Desmethyl Imatinib in Rats

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Xian-yun Liu ◽  
Tao Xu ◽  
Wan-shu Li ◽  
Jun Luo ◽  
Pei-wu Geng ◽  
...  
Keyword(s):  
Single Dose ◽  
Pharmacokinetic Parameters ◽  
Control Group ◽  
Term Study ◽  
Long Term Study ◽  
Short Term Study ◽  
Term Administration ◽  
Group A ◽  
Group B

The purpose of this study was to determine the effect of apigenin on the pharmacokinetics of imatinib and N-desmethyl imatinib in rats. Healthy male SD rats were randomly divided into four groups: A group (the control group), B group (the long-term administration of 165 mg/kg apigenin for 15 days), C group (a single dose of 165 mg/kg apigenin), and D group (a single dose of 252 mg/kg apigenin). The serum concentrations of imatinib and N-desmethyl imatinib were measured by HPLC, and pharmacokinetic parameters were calculated using DAS 3.0 software. The parameters ofAUC(0-t),AUC(0−∞),Tmax,Vz/F, andCLz/Ffor imatinib in group B were different from those in group A (P<0.05). Besides,MRT(0−t)andMRT(0−∞)in groups C and D differed distinctly from those in group A as well. The parameters ofAUC(0-t)andCmaxfor N-desmethyl imatinib in group C were significantly lower than those in group A (P<0.05); however, compared with groups B and D, the magnitude of effect was modest. Those results indicated that apigenin in the short-term study inhibited the metabolism of imatinib and its metabolite N-desmethyl imatinib, while in the long-term study the metabolism could be accelerated.

scholarly journals Preservation of long-term neurocognitive function by hippocampal avoidance whole-brain radiotherapy in patients with brain metastases.

2019 ◽  
Vol 5 (suppl) ◽  
pp. 124-124
Author(s):  
Buhai Wang ◽  
Shiwei Fu ◽  
Yuxiang Huang
Keyword(s):  
Tumor Recurrence ◽  
Whole Brain Radiotherapy ◽  
Neurocognitive Function ◽  
Whole Brain ◽  
Brain Radiotherapy ◽  
Hippocampal Avoidance ◽  
Significant Difference ◽  
Group A ◽  
Group B

124 Background: To investigate the preservation of long-term neurocognitive function in patients after hippocampal avoidance whole-brain radiotherapy (HA-WBRT). Methods: For the retrospective analysis, 50 patients diagnosed with brain metastases were selected and divided into two groups from 2015-01-01 to 2017-12-31 at the Department of Oncology, Jiangsu Subei People's Hospital. Group A (n=27) was hippocampal avoidance whole-brain radiotherapy group; group B (n=23) was whole brain radiation therapy (WBRT) group. Neurocognitive function was statistically analyzed at 3, 6, 9, 12, and 24 months after radiotherapy, as scored by the MMSE (Mine-Mental State Examination) scales and the MoCA (Montreal Cognitive Assessment) scales. The OS, PFS and tumor recurrence sites of the two groups was also analyzed. Results: After 12, 24 months after radiotherapy, there was a significant difference between the two groups. The cognitive function of the hippocampal protection group was significantly higher than that of the non-hippocampal protection group (P<0.05). There was no significant difference in OS (P=0.2) and PFS (P=0.18) between the two groups. 14 patents in group A and 12 patents in group B had brain tumor recurrence after radiation, only one patient in group A occurred 5 mm within the edge of the hippocampus (P>0.05). Conclusions: First, HA-WBRT has a protective effect on long-term neurocognitive function. Second, there was no statistically significant different on OS and PFS in patients who underwent HA-WBRT or WBRT. Third, HA-WBRT didn’t increase the risk of brain tumor recurrence within the edge of the hippocampus.

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