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981.
Bicaval and standard techniques in orthotopic heart transplantation: medium-term experience in cardiac performance and survival. 总被引:6,自引:0,他引:6
T Aziz M Burgess R Khafagy A Wynn Hann C Campbell A Rahman A Deiraniya N Yonan 《The Journal of thoracic and cardiovascular surgery》1999,118(1):115-122
OBJECTIVE: The aim of this study was to compare the medium-term results of right heart pressures, tricuspid valve dysfunction, overall cardiac performance, and survival between the bicaval and standard techniques. METHOD: Between 1991 and 1997, 201 heart transplantations were performed in our center. Right heart catheterization was performed up to 12 months after transplantation. Echocardiography was used to assess left ventricular and tricuspid valve function. RESULT: The standard technique was used in 105 cases, and the bicaval technique was used in 96 cases. There was no difference in the age, preoperative parameters, pulmonary hemodynamics, or ischemic time between the 2 groups. Right atrial pressure (4.3 +/- 4.0 mm Hg for the bicaval vs 10.9 +/- 4.8 mm Hg for standard technique) and mean pulmonary artery pressure (17.5 +/- 5.3 mm Hg and 22.5 +/- 5.2 mm Hg, respectively) were lower for the bicaval recipients up to 12 months after the operation (P =.001 and. 01, respectively). Left ventricular ejection fraction was higher for the recipients of the bicaval technique up to the most recent measurement (P =.005). The prevalence of moderate or severe tricuspid regurgitation was higher in the recipients of the standard technique up to the most recent measurement (28% vs 7%; P =.02). The actuarial survival at 1, 3, and 5 years was 74%, 70%, and 62% for the recipients of the standard technique versus 87%, 82%, and 81% for the recipients of the bicaval technique (P <.03, <.04, and <.02, respectively). CONCLUSION: The bicaval technique maintains good left ventricular function, lower incidence and severity of tricuspid valve dysfunction, and improved survival compared with the standard technique. 相似文献
982.
T Aziz M Burgess A Rahman C Campbell A Deiraniya N Yonan 《The Journal of thoracic and cardiovascular surgery》1999,118(4):733-739
OBJECTIVES: The purpose of this study was to analyze the impact of the zonal allocation system for thoracic organs on the outcome of our transplant activity. METHODS: We analyzed the results of thoracic transplants performed between 1987 and 1998. The transplants were divided into 3 groups: local donors retrieved by our team (171 hearts and 61 lungs; DL group); distant donors retrieved by our team (58 hearts and 35 lungs; DD group); and distant donors retrieved by other teams (51 hearts and 41 lungs; DX group). RESULTS: No significant differences were observed among the groups in early postoperative events for either heart or lung transplantation. Heart transplants: Cardiac index was 2.6 +/- 0.4 L/m(2) for the DL group, 2.7 +/- 0.6 L/m(2) for the DD group, and 2.5 +/- 0.7 L/m(2) for the DX group (P =.4). The 30-day mortalities were 9.1%, 9.1%, and 8.3% ( P =.5) and the 1-year survivals 83%, 80%, and 82% ( P =.4) for the DL, DD, and DX groups, respectively. Lung transplants: Alveolar-arterial oxygen gradient was 358 +/- 19 mm Hg for the DL group, 345 +/- 17 mm Hg for the DD group, and 329 +/- 21 mm Hg for the DX group (P =.07). The 30-day mortalities were 9.9%, 10.5%, and 12.8% (P =.2) and the 1-year survivals 79%, 75%, and 77% (P =.3) for the DL, DD, and DX groups, respectively. CONCLUSION: Zonal allocation for thoracic organs has been successfully applied to our program. Using donor organs retrieved by other teams, we have achieved equivalent outcomes for both heart and lung transplantation. 相似文献
983.
Laterality effects of human pudendal nerve stimulation on corticoanal pathways: evidence for functional asymmetry 总被引:2,自引:0,他引:2
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BACKGROUND: Although motor and sensory pathways to the human external anal sphincter are bilateral, a unilateral pudendal neuropathy may still disrupt anal continence. Anal continence can, however, be preserved despite unilateral pudendal damage, and so to explain those differing observations, we postulated that pudendal innervation might be asymmetric. AIMS: To explore the individual effects of right and left pudendal nerve stimulation on the corticofugal pathways to the human external anal sphincter and thus assess evidence for functional asymmetric pelvic innervation. METHODS: In eight healthy subjects, anal sphincter electromyographic responses, evoked to transcranial magnetic stimulation of the motor cortex, were recorded 5-500 msec after digital transrectal electrical conditioning stimuli applied to each pudendal nerve. RESULTS: Right or left pudendal nerve stimulation evoked anal responses of similar latencies but asymmetric amplitudes in six subjects: dominant responses (>50% contralateral side) from the right pudendal in four subjects and from the left in two. Cortical stimulation also evoked anal responses with amplitude 448 (121) microV and latency 20.9 (1.1) msec. When cortical stimulation was preceded by pudendal nerve stimulation, the cortical responses were facilitated at interstimulus intervals of 5-20 msec. Dominant pudendal nerve stimulation induced greater facilitation of the cortically evoked responses than the non-dominant nerve. CONCLUSIONS: Cortical pathways to the external anal sphincter are facilitated by pudendal nerve conditioning, in an asymmetric manner. This functional asymmetry may explain the presence and absence of anal incontinence after unilateral pudendal nerve injury. 相似文献
984.
Distal versus proximal arm tremor in multiple sclerosis assessed
by visually guided tracking tasks 总被引:2,自引:1,他引:1
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X. Liu R Miall T. Aziz J. Palace J. Stein 《Journal of neurology, neurosurgery, and psychiatry》1999,66(1):43-47
OBJECTIVES—To compareaction tremor (AT) during manual tracking in normal subjects andpatients with multiple sclerosis with tremor (MS-tremor group) andwithout tremor (MS-no tremor group), and to differentiate tremoroccurring predominantly around the distal joint from that involving theproximal joints of the arm.
METHODS—Subjectsperformed both a visually guided ramp tracking task using wristflexion/extension and a whole arm circle tracking task using shouldermovement. Action tremor at the wrist or shoulder was computed as the SDof the tracking velocity. The ratio of wrist:arm tremor was thencalculated to differentiate distal from proximal tremor in the testedarm. Frequency spectra of the records were also examined.
RESULTS—During wristtracking, AT in patients with multiple sclerosis contained a majorfrequency component at 4-5 Hz; the frequency was slightly lower duringwhole arm tracking. The ratio of wrist:arm tremor was significantlyhigher in the MS-tremor group. Of 12tested arms, eight had tremorsignificantly weighted towards the distal joint, only one towards theproximal joint, and three had a ratio inside the control range.
CONCLUSIONS—AT in thearms of patients with multiple sclerosis can be effectivelydifferentiated into proximal or distal using these two differenttracking tasks. Despite the variability of the effects of multiplesclerosis, most of the AT was distal rather than proximal in this groupof patients. Possibly conduction block along the corticocerebellocortical pathways caused this distal tremor.
相似文献
METHODS—Subjectsperformed both a visually guided ramp tracking task using wristflexion/extension and a whole arm circle tracking task using shouldermovement. Action tremor at the wrist or shoulder was computed as the SDof the tracking velocity. The ratio of wrist:arm tremor was thencalculated to differentiate distal from proximal tremor in the testedarm. Frequency spectra of the records were also examined.
RESULTS—During wristtracking, AT in patients with multiple sclerosis contained a majorfrequency component at 4-5 Hz; the frequency was slightly lower duringwhole arm tracking. The ratio of wrist:arm tremor was significantlyhigher in the MS-tremor group. Of 12tested arms, eight had tremorsignificantly weighted towards the distal joint, only one towards theproximal joint, and three had a ratio inside the control range.
CONCLUSIONS—AT in thearms of patients with multiple sclerosis can be effectivelydifferentiated into proximal or distal using these two differenttracking tasks. Despite the variability of the effects of multiplesclerosis, most of the AT was distal rather than proximal in this groupof patients. Possibly conduction block along the corticocerebellocortical pathways caused this distal tremor.
相似文献
985.
S Sheldon N A Yonan T N Aziz P S Hasleton A N Rahman A K Deiraniya C S Campbell P A Dyer 《Transplantation》1999,68(4):515-519
BACKGROUND: We report a consecutive single center series of 261 patients who received first orthotopic heart transplants from 1986 to 1997. The 1- and 5-year graft survivals were 78 and 68%. The influence of histocompatibility was investigated by comparing graft survival and numbers of treated rejection episodes with HLA-A, -B, and -DR mismatches over different time periods. FINDINGS: Recipients with six mismatches for HLA-A+-B+-DR combined (13.4%) had reduced survival at 7 years (47%) when compared with other recipients (64%). In the first year of transplant, recipients with four HLA-A+-B mismatches had significantly reduced actuarial graft survival (P=0.03) with the greatest influence apparent at 6 months [0-3 mismatches (n=193) 85% versus 4 mismatches (n=68) 69%; P=0.005, OR=2.1]. For 182 recipients with functioning hearts at 1 year, the number of rejection episodes treated within this time was strongly influenced by HLA-DR mismatch [0 DR mismatch (n=15) mean 1.2 rejection episodes versus 1 DR mismatch (n=76) mean 2.7 rejection episodes versus 2 DR mismatches (n=91) mean 3.8 rejection episodes: P=0.0002]. Of these 182 transplants, recipients who had more than four treated rejection episodes during the first year had a significantly reduced 7- year survival [<5 rejection episodes (n=133) 85% versus more than four rejection episodes (n=49) 66%; P=0.02, OR=3.4], as did those with two HLA-DR mismatches [0+1 mismatch (n=91) 87% versus 2 mismatches (n=91) 70%; P<0.05, OR=2.4]. INTERPRETATION: We show that graft loss in the first 6 months of transplant is significantly influenced by four HLA-A+-B mismatches. HLA-DR mismatch significantly increases the number of rejection episodes within the first year, without influencing graft survival. After 12 months both >4 rejection episodes in the first year and two HLA-DR mismatches are markers for late graft loss. We postulate that immunological graft loss in the first 6 months is dominated by the direct allorecognition pathway driven by HLA-DR mismatch. This mechanism is later lost or suppressed. Our data highlight HLA-DR mismatch as a marker for late graft loss and we show an advantage to avoiding transplanting hearts with six HLA-A+-B+-DR mismatches and to minimizing HLA-DR mismatches whenever possible. 相似文献
986.
Identification of the optimal parameters for recording cortical potentials evoked by mechanical stimulation of the human oesophagus 总被引:2,自引:0,他引:2
Cortical evoked potentials (CEP) have been recorded in response to both electrical stimulation (ES) and mechanical stimulation (MS) of the oesophagus. While the optimal parameters for recording reproducible oesophageal CEP to ES have recently been established, they have not yet been determined for MS, and reported CEP to MS show considerable variability. This study aimed to identify the optimal parameters required to record reproducible MS induced CEP. CEP were recorded from the vertex (Cz) in six subjects (one female; age range 23-47 years). MS was performed 5 cm above the lower oesophageal sphincter by rapidly inflating a 2-cm long silicone balloon at a frequency of 0.2 Hz. The rise time to maximum inflation was 165 ms. In order to determine the minimum number of stimuli required to produce optimal signal-to-noise quality, we acquired data in runs of 25, 50, 100 and 300 stimuli and to determine the stimulation intensity that produced the shortest latency and the largest amplitude CEP, we averaged four runs of 50 stimuli at five different intensities ranging from sensory threshold to pain. CEP reproducibility was then assessed in three subjects on three separate occasions using parameters determined from these measurements. We found that optimal signal-to-noise quality was achieved by averaging four runs of 50 stimuli; that P1 latency was shortest and P1-N1 amplitude largest at intensities of 75% and pain threshold and that highly reproducible CEP were obtained in all individuals. We conclude that it is possible to obtain highly reproducible oesophageal CEP to MS which can now be compared to those obtained by ES in order to identify which is most suitable for clinical studies. 相似文献
987.
Hina Qamar Adil Saeed Mohammad Owais Touseef Hussain Kashif Hussain Aziz ur Rahman Sarfraz Ahmed Sachin Kumar Zulfiqar Ahmad Khan 《Materials》2021,14(21)
Worldwide, bacterial resistance to beta-lactam antibiotics is the greatest challenge in public health care. To overcome the issue, metal-based nanoparticles were extensively used as an alternative to traditional antibiotics. However, their unstable nature limits their use. In the present study a very simple, environmentally friendly, one-pot synthesis method that avoids the use of organic solvents has been proposed to design stable, novel nanocomposites. Formulation was done by mixing biogenic copper oxide (CuO) nanomaterial with glycerol and phospholipids isolated from egg yolk in an appropriate ratio at optimum conditions. Characterization was done using dynamic light scattering DLS, Zeta potential, high performance liquid chromatography (HPLC), and transmission electron microscopy (TEM). Further, its antibacterial activity was evaluated against the extended-spectrum beta-lactamase strains based on zone of inhibition and minimal inhibitory concentration (MIC) indices. Results from this study have demonstrated the formulation of stable nanocomposites with a zeta potential of 34.9 mV. TEM results indicated clear dispersed particles with an average of 59.3 ± 5 nm size. Furthermore, HPLC analysis of the egg yolk extract exhibits the presence of phospholipids in the sample and has significance in terms of stability. The newly formed nanocomposite has momentous antibacterial activity with MIC 62.5 μg/mL. The results suggest that it could be a good candidate for drug delivery in terms of bactericidal therapeutic applications. 相似文献
988.
Qura Tul Ain Idrees Nazish Gul Muhammad Amber Fareed Salman Aziz Mian Danish Muzaffar Muhammad Nasir Aqif Anwar Chaudhry Sultan Akhtar Syed Zubairuddin Ahmed Abdul Samad Khan 《Materials》2021,14(24)
This study aimed to modify an EQUIA coat (EC; GC, Japan) by incorporating 1 and 2 wt.% of zinc oxide (ZnO; EC-Z1 and EC-Z2) and titanium dioxide (TiO2; EC-T1 and EC-T2) nanoparticles, whereby structural and phase analyses were assessed using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), respectively. Thermogravimetric analysis/differential scanning calorimetry, micro-hardness, and water absorption analyses were conducted, and the microstructure was studied by scanning electron microscopy/energy-dispersive spectroscopy. FTIR spectra showed a reduction in peak heights of amide (1521 cm−1) and carbonyl (1716 cm−1) groups. XRD showed peaks of ZnO (2θ ~ 31.3°, 34.0°, 35.8°, 47.1°, 56.2°, 62.5°, 67.6°, and 68.7°) and TiO2 (2θ ~ 25.3°, 37.8°, 47.9, 54.5°, 62.8°, 69.5°, and 75.1°) corresponding to a hexagonal phase with a wurtzite structure and an anatase phase, respectively. Thermal stability was improved in newly modified materials in comparison to the control group. The sequence of obtained glass transitions was EC-T2 (111 °C), EC-T1 (102 °C), EC-Z2 (98 °C), EC-Z1 (92 °C), and EC-C (90 °C). EC-T2 and EC-T1 showed the highest (43.76 ± 2.78) and lowest (29.58 ± 3.2) micro-hardness values. EC showed the maximum water absorption (1.6%) at day 7 followed by EC-T1 (0.82%) and EC-Z1 (0.61%). These results suggest that EC with ZnO and TiO2 nanoparticles has the potential to be used clinically as a coating material. 相似文献
989.
A 22-year-old male awoke with right foot drop and numbness. Nerve conduction studies, sural nerve biopsy, and molecular genetic analysis were consistent with hereditary neuropathy with liability to pressure palsy (HNPP). Two months later he developed involuntary flexion/extension movements of the right toes with associated intermittent dystonic flexion of the right foot. Over the next 2 months these movements spread to the left foot and hand and myoclonus of the left trapezius and rhomboid appeared. This is the first case report of moving toes syndrome and segmental myoclonus in association with HNPP. The temporal and topographic patterns of spread of the abnormal movements suggest a central mechanism probably induced by peripheral pathology. © 1997 John Wiley & Sons, Inc. Muscle Nerve 20: 881–883, 1997 相似文献
990.