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1.
Khaled Adil Marija Popovic Fabio L. Cury Sergio L. Faria Marie Duclos Luis Souhami 《Practical radiation oncology》2019,9(1):24-28
Purpose
This study aimed to investigate 3 planning target volume (PTV) margin expansions and determine the most appropriate volume to be used in bladder preservation therapy when using daily cone beam computed tomography (CBCT). We aimed to establish whether a smaller PTV expansion is feasible without risking geographical miss.Methods and materials
The study included patients with bladder cancer who were treated with a hypofractionated course of radiation therapy delivered with intensity modulated radiation therapy. The clinical target volume (CTV) was the whole empty bladder, and the PTV consisted of a 1.5-cm margin around the bladder (PTV1.5 cm). Patients underwent daily CBCT imaging before treatment to assess the bladder volume and ensure accurate positioning. We investigated 2 additional smaller PTV margin expansions to determine the most appropriate volume to be used with CBCT as a daily image guided radiation therapy modality. These margins were created retrospectively on every CBCT. The first additional volume was a uniform PTV margin of the surrounding 1 cm (PTV1 cm). When considering that the majority of the internal bladder movement was due to the variation in filling that occurs in the superior and anterior directions, a second volume of an anisotropic PTV margin with a 1.5-cm superior/anterior and 1 cm in other directions (PTV1/1.5 cm) was created. We recorded the frequency and measured the volume of bladder falling out of each PTV based on the daily CBCT.Results
For the purpose of this study, we considered an arbitrary 5 cm3 of CTV falling out of the designated PTV as a clinically significant volumetric miss. The frequency of such a miss when applying the uniform PTV1 cm was 1%. However, when applying the uniform PTV1.5 cm and anisotropic PTV1/1.5 cm margins, the frequency was 0.5% and 0.5%, respectively.Conclusions
The anisotropic PTV expansion of 1.5 cm superiorly and anteriorly and 1 cm in all other directions around the bladder (CTV) provides a safe PTV approach when daily CBCT imaging is used to localize an empty bladder. 相似文献2.
Dr. Menon Raj Gopal M.Ch. AlDelamie Taha FRCS Valliathu John FRCS Zacharias Sunny FRCS Lawati Al Adil FRCS Venkatraman M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):173-177
Background Despite improving surgical techniques, treatment of heart valve disease in children remains controversial. Somatic growth
and adequate anticoagulation are of concern when children undergo valve replacement. We conducted this study to evaluate the
performance of valves in this age group.
Methods 42 children under the age of 13 years who underwent valve replacement were included in this study. Totally, 50 valves were
implanted in 42 patients: 48 were mechanical prostheses, two were bioprosthetic both in pulmonary position. 37 (74%) valves
were implanted in mitral position, 10 (20%) in aortic position, 1 (2%) in tricuspid position and 2 (4%) in pulmonary position.
Preoperatively, 14 (33,3%) patients were in New York Heart Association (NYHA) class IV, while 27 (64.2%) were in NYHA class
III.
Results There were 2 (4.7%) hospital deaths and 2 (4.7%) late deaths while 2 (4.7%) patients were lost to follow up. The mean follow
up period was 9.4 yrs. 35 (83.3%) patients are in NYHA Class I and free of all medications except warfarin. 3 (7.1%) patients
have undergone 5 successful pregnancies. The median INR was 2.23. Major thrombo-embolic episode occurred in 1 (2.3%) patient.
Conclusions In view of the problems of sizing, anticoagulation and need for re-operation at an early age, there is a reluctance to replace
valves in children. This study shows that despite these problems, valve replacement can be undertaken safely and successfully
in children, when repair has failed or not technically feasible. 相似文献
3.
Wistar strain adult male and female rats were given 25, 50 and 75% less food than an ad libitum-fed group of rats for 45 d and the effects of food restriction on hepatic drug metabolizing enzymes, microsomal electron transport components, NADPH-dependent lipid peroxidation and glutathione-S-transferase activities were studied. Compared to ad libitum-fed controls, the cytochrome P-450 levels were higher in food restricted male rats, while they were lower in food restricted females. The activities of NADPH cytochrome c reductase were lower in food restricted females than in ad libitum-fed controls. The activities of drug metabolizing enzymes, aminopyrine N-demethylase and acetanilide hydroxylase were higher in food restricted males, whereas in food restricted females these activities were lower than in respective groups fed ad libitum. Microsomal, NADPH-dependent lipid peroxidation was higher in 25 and 50% food restricted females while in 50 and 75% food restricted males it was lower than in ad libitum controls of the same sex. The cytosolic glutathione-S-transferase activities were lower in food restricted rats of both the sexes than in the same sexed controls. Another group of male and female rats were given 75% less food than the ad libitum-fed rats and refed for 3 d prior to killing. Here also, the effects of restriction were different between sexes. It is concluded that hepatic microsomal mixed-function oxidase system (MFOS) is altered due to feed restriction and food restriction followed by refeeding, in a sex-related manner. 相似文献
4.
Mehmet Oguz Yenidunya Mustafa Erol Demirseren Serdar Gorkem Bulent Adil Tasbas Candemir Ceran 《European journal of plastic surgery》2007,29(7):327-330
Nonunion in the forearm following a radioulnar fracture is one of the nightmares of the orthopedic surgeon. Fortunately, it
is rare. We treated a large bone defect of the forearm, using a vascularized fibular graft after excision of the unhealed
bone segment in a 10-year-old boy with neurofibromatosis. This situation followed a double fracture that had been operated
on several times using conventional methods. Following the debridement of the unhealthy tissues in the pseudoarthrotic region,
the vascularized fibula was placed on the dorsal surface of the proximal radius fragment. The distal fragment of the radius
was inserted into the fibular cavity and fixation was established with a Kirschner wire distally and with a plate proximally.
Only two screws were used to fix the plate. The peroneal artery was anastomosed with the radial artery; one of its venae comitantes
was anastomosed with the cephalic vein in an end-to-end fashion. After surgery, the elbow was immobilized at 90 degrees of
flexion with a splint for 6 weeks. One year after surgery, forearm stabilization and elbow and hand functions were very satisfactory.
However, because the distal epiphyses of the bones were destroyed following the repeated surgery and the original trauma itself,
a very prominent difference between the two forearms occurred, suggesting the need for bone lengthening in the future. By
presenting this case we would like to conclude that one can expect good bone healing with a vascularized bone transfer in
these cases when there is not enough space to place screws, but support can be provided by an external splint and K wire. 相似文献
5.
Dr. Adil Kabeer M.B.B.Ch. Sigurdur Gunnlaugsson M.D. Charles Coren M.D. 《Diseases of the colon and rectum》1995,38(8):866-872
PURPOSE: A retrospective, 12-year review of neonatal necrotizing enterocolitis was undertaken at a county hospital, with emphasis on presentation signs and symptoms. METHODS: Eighty-two patients with presence of intramural air were included in the study. The following signs and symptoms were studied: evidence of respiratory distress, use of umbilical catheters, white blood cell count and temperature at presentation, time interval from birth to diagnosis and time interval from diagnosis to operative intervention, presence of intramural air, air in biliary tree or free air, changes in abdominal girth, and presence of occult or gross blood in stools. Comparison was done among infants who had surgical or medical treatment, premature and full-term infants, and infants who had neonatal necrotizing enterocolitis less than or more than 20 days after birth. RESULTS: Eleven patients had a fatal outcome, with an overall survival of 87 percent. Sixty-four patients were treated medically and 18 had operative treatment. Mortality of the surgically treated group was 44 percent. Neonates who had surgical intervention had a left shift of the white blood cell count more commonly present, and all had documented abdominal distention. There were 62 premature and 20 full-term neonates in the group. Full-term neonates developed neonatal necrotizing enterocolitis earlier after birth (5.3 days compared with 15.3 days in the premature neonate group). Full-term neonates had a better prognosis in our series. Presentation of symptoms more than 20 days after birth did not change outcome. CONCLUSION: Our results reflect the experience of a community-based hospital. Clinical acumen remains the cornerstone of diagnosis and management. 相似文献
6.
S. F. Hashmi S. A. Hasan M. Aslam A. Shakoor 《Indian journal of otolaryngology and head and neck surgery》1995,47(2):119-121
100 cases of either sex 96 males and 4 females in their mean age group of 45 year ± 14.51 standard deviation were selected for this study to analyse the Hearing Acuity in the post spinal analgesia period during a period of eight months in the E.N.T department of the J.N. Medical College A.M.U. Aligarh. The size of the needle used for spinal analgesia was 22G and the equipment for Audiometry was the pure tone Audiometer. Pure tone Audiometry was done pre-operatively and then on the 1st, 3rd, 5th and 12th subsequent post-operative days and then after six months. It was found that 12% of the patients showed incidence of mild hearing loss. However, the loss was transient, reversible, within low frequency range (250, 500, 1000 Hz), and no patient suffered from any permanent hearing loss. 相似文献
7.
Glyceraldehyde-3-phosphate dehydrogenase: Nuclear translocation participates in neuronal and nonneuronal cell death
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Akira Sawa Adil A. Khan Lynda D. Hester Solomon H. Snyder 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(21):11669-11674
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein levels increase in particulate fractions in association with cell death in HEK293 cells, S49 cells, primary thymocytes, PC12 cells, and primary cerebral cortical neuronal cultures. Subcellular fractionation and immunocytochemistry reveal that this increase primarily reflects nuclear translocation. Nuclear GAPDH is tightly bound, resisting extraction by DNase or salt treatment. Treating primary thymocytes, PC12 cells, and primary cortical neurons with antisense but not sense oligonucleotides to GAPDH prevents cell death. Because cell-death-associated nuclear translocation of GAPDH and antisense protection occur in multiple neuronal and nonneuronal systems, we propose that GAPDH is a general mediator of cell death and uses nuclear translocation as a signaling mechanism. 相似文献
8.
Fred Poordad Robert Gish Adil Wakil Richard Garcia-Kennedy Paul Martin Francis Y. Yao 《American journal of transplantation》2003,3(11):1413-1417
Non-alcoholic fatty liver disease (NAFLD) is an increasingly recognized clinico-pathologic entity typically associated with obesity, type II diabetes and hyperlipidemia. It has been noted to recur after orthotopic liver transplantation (OLT). We report four patients who developed de novo NAFLD within 3 months of OLT without the typical predisposing factors of diabetes mellitus or obesity. Three of the four patients underwent OLT for hepatitis C-related cirrhosis, and the other for alcoholic cirrhosis. Examination of the liver explants revealed no evidence of steatosis. No surreptitious alcohol use or a drug-induced process could be identified in these patients. Treatment of recurrent hepatitis C infection in one patient with interferon and ribavirin led to sustained suppression of the viral RNA to undetectable levels, but no improvement in histology or liver enzymes. All four patients had histologic evidence of preservation injury on the initial post-OLT biopsies, but the significance of this finding in relationship to the development of NAFLD is unknown. NAFLD can develop without any of the known predisposing conditions after transplantation, and this raises further questions about the pathogenesis of this condition . 相似文献
9.
Approximately 5% of Americans over age 65, or 1.5 million individuals, currently reside in the nations's 20,000 nursing homes. The authors present material that lead to three conclusions about this population. First, nutritional deficiencies are common underlying causes of adverse clinical outcomes. Second, nutritional deficiencies are frequently not recognized. Third, opportunities for preventing or correcting undernutrition exist, provided that the significant and reversible nature of the nutrient deficiencies are identified. 相似文献
10.
Respiratory syncytial virus (RSV) is a recognised cause of lower respiratory tract infection in infants and young children. It causes severe respiratory disease in preterm infants with or without chronic lung disease. This study, conducted at Waterford Regional Hospital, evaluates the incidence of RSV infection in hospitalised children, its seasonal variation, and effectiveness of its prevention. Thirty eight percent of admitted children with bronchiolitis were RSV positive in the year 1999 November to March is the peak season for this infection. A highly selected group of 7 preterm children with or without chronic lung disease received Palivizumab prophylaxis. Not one of them acquired RSV infection. The high cost of Palivizumab was the main factor for its restricted use. Palivizumab was found to be effective in preventing RSV infection in our study. Since we had a small number of patients, further studies are needed for its economic and judicious use. Respiratory syncytial virus (RSV) is virulent easily transmissible and the most common cause of lower respiratory tract disease in children of less than 2 years of age. Up to 98% of children attending day care will be infected in single RSV season. Between 0.5% and 3.2% of children with RSV infection require Hospitalisation. Approximately 90,000 hospital admissions and 4500 deaths per year were reported in United States. In Ireland 2807 patients were admitted with Bronchiolitis in 1998. Major risk factors for hospitalisation due to RSV are Prematurity, chronic lung disease, congenital heart disease, compromised immunity and age younger then 6 weeks in otherwise healthy children. No effective treatment of RSV positive bronchiolitis beside supportive care in the form of adequate nutrition and oxygen therapy is available. Antiviral therapies such as Ribavirin has not been proved to be effective in RSV infection. Bronchodilators show variable results. Corticosteroids were not found effective. There is no effective vaccine available as yet. There is no proven method for active immunity. Various immunoglobulins are available for acquiring passive immunity against RSV infection. PREVENT study group in Jan. 1997 showed intravenous immunoglobulin (RSV- IGIV) use in reducing 41% to 63% hospitalisation in RSV patients. But RSV-IGIV was not licensed outside the United States because of risk of transmission of blood borne products, difficulty in administration ie. intravenous access, large fluid volume (15 ml/kg), high protein load (750 mg/kg), shortage of supply and need to postpone live vaccine (eg. MMR, varicella). monoclonal antibody Palivizumab was developed for prophylaxis against RSV infection. Clinical safety and efficacy of Palivizumab were demonstrated in IMpact trial published in Sept. 1998. Reduction in hospitalisation up to 55% was noted in this study. It was a pivotal randomised, double blind, placebo controlled phase 3 study conducted in 139 centres throughout Canada, United States and United Kingdom. We looked at our experience in patients admitted with bronchiolitis in Waterford Regional Hospital. We described the outcome of carefully selected Seven children of high risk group for Palivizumab prophylaxis. Its clinical Implications and cost effectiveness was evaluated in this study. 相似文献