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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.
Recent work demonstrated that crotoxin, the main toxin of Crotalus durissus terrificus venom, inhibits macrophage spreading and phagocytic activities. The crotoxin molecule is composed of two subunits, an acidic non-toxic and non-enzymatic polypeptide named crotapotin and a weakly toxic basic phospholipase A2 (PLA2). In the present work, the active subunit responsible for the inhibitory effect of crotoxin on macrophage function was investigated. Peritoneal macrophages harvested from naive rats were used. Crotapotin (2.12, 3.75, or 8.37 nM/ml), added for 2 h to the medium of peritoneal cell incubation, did not modify the spreading and phagocytic activities of these cells. On the other hand, the PLA2 (1.43, 2.86, or 6.43 nM/ml) subunit caused a significant reduction (30, 33, and 35%, respectively) of the spreading activity. The PLA2 also inhibited the phagocytosis of opsonised zymosan, opsonised sheep erythrocytes, and Candida albicans, indicating that this inhibitory effect is not dependent on the type of receptor involved in the phagocytosis process. The inhibitory effect of PLA2 was not due to loss of cell membrane integrity, since macrophage viability was higher than 95%. These findings indicate that the inhibitory effect of crotoxin on macrophage spreading and phagocytic activities is caused by the phospholipase A2 subunit. 相似文献
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Suhny Abbara Sanjeeva Kalva Ricardo C. Cury Eric M. Isselbacher 《Journal of Cardiovascular Computed Tomography》2007,1(1):40-54
The clinical presentation of diseases involving the thoracic aorta ranges from a large number of asymptomatic patients with clinically undetectable thoracic aortic aneurysm to patients with symptoms of severe chest pain as a result of acute aortic dissection. Thoracic aortic disease often remains undiagnosed until a life-threatening complication occurs or the disease is discovered serendipitously on imaging studies performed for other purposes. Multidetector row computed tomography (MDCT) imaging of the aorta is used to diagnose various acute and chronic conditions, including aortic aneurysms, aortic dissection, intramural hematoma, penetrating atherosclerotic ulcer, traumatic injury, rupture, inflammatory disorders, and congenital malformations. This review illustrates the wide range of MDCT imaging findings of thoracic aortic disease. 相似文献
8.
Rheumatic heart disease: proinflammatory cytokines play a role in the progression and maintenance of valvular lesions 总被引:3,自引:0,他引:3 下载免费PDF全文
Guilherme L Cury P Demarchi LM Coelho V Abel L Lopez AP Oshiro SE Aliotti S Cunha-Neto E Pomerantzeff PM Tanaka AC Kalil J 《The American journal of pathology》2004,165(5):1583-1591
Heart lesions of rheumatic heart disease (RHD) patients contain T-cell clones that recognize heart proteins and streptococcal M peptides. To functionally characterize heart-infiltrating T lymphocytes, we evaluated their cytokine profile, both directly in situ and in T-cell lines derived from the heart (HIL). Interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-4, and IL-10 expressions were characterized in 20 heart tissue infiltrates from 14 RHD patients by immunohistochemistry. IFN-gamma-, TNF-alpha-, and IL-10-positive cells were consistently predominant, whereas IL-4 was scarce in the valves. In agreement with these data, the in vitro experiments, in which 13 HILs derived from heart samples of eight patients were stimulated with M5 protein and the immunodominant M5 (81-96) peptide, IL-4 was detected in HIL derived from the atrium (three of six) but not from the valve (zero of seven). IFN-gamma and IL-10 production were detected in culture supernatants in 11 of 13 and 6 of 12 HILs, respectively. The predominant IFN-gamma and TNF-alpha expression in the heart suggests that Th1-type cytokines could mediate RHD. Unlike in reversible myocardium inflammation, the significantly lower IL-4 expression in the valvular tissue (P = 0.02) may contribute to the progression of the RHD leading to permanent valvular damage (relative risk, 4.3; odds ratio, 15.8). The lack of IL-4 in vitro production by valve-derived HIL also emphasizes the more severe tissue destruction in valves observed in RHD. 相似文献
9.
Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
10.
This study analyses the influence of female and male patient age and human
menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and
live birth rates with ovulation stimulation using HMG in combination with
intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI
treatment cycles in 184 patients carried out at a university fertility
centre were analysed in a retrospective fashion. The main outcomes measured
were clinical pregnancy rates and live birth rates. Increased female
partner age (> or = 35) and male partner age (> or = 40) were found
to negatively influence pregnancy rates with HMG/ IUI therapy. In addition,
this study demonstrated a critical threshold of HMG requirements beyond
which pregnancy did not occur. No pregnancies occurred in treatment cycles
requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular
maturity, irrespective of patient age. In conclusion, female partner age,
male partner age, and HMG requirements all significantly influence
pregnancy rates with HMG/IUI therapy.
相似文献