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1.

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.
CD16, the type III receptor for IgG, is expressed on neutrophils, natural killer cells, and some T lymphocytes, mast cells, and activated monocytes but not on cells of the B-lymphocyte lineage including plasma cells. It is also produced in a soluble form found in serum. We analyzed sera from 165 multiple-myeloma patients, 29 patients with monoclonal gammopathies of unknown significance, and 20 normal disease-free donors. We found that the level of soluble CD16 was significantly decreased in sera from patients with multiple myeloma compared to sera from healthy and monoclonal gammopathies of unknown significance donors (P=0.0001). In addition, a stage-dependent decrease in soluble CD16 was observed, with a highly significant difference (P=0.004) between stage I and stage II+III myeloma patients. The correlation between the myeloma stage and the serum level of soluble CD16, which is related to the host response, was found to be more sensitive than that of 2-microglobulin, which reflects the tumor burden. The concomitant evaluation of the serum levels of these two markers allows better staging and therefore has a more precise prognostic value.  相似文献   
3.
H Duclos  M C Maillot    P Galanaud 《Immunology》1982,46(3):595-601
We describe selective effects of azathioprine (Az) on T-cell subpopulations regulating the primary in vitro antibody response of mouse spleen cells to the T-independent antigen TNP-polyacrylamide. This response is susceptible to the effect of two kinds of non-specific suppressor cells: (i) spontaneously-induced suppressor, generated after 4-5 days culture in the presence of 2 micrograms/ml of concanavalin A (Con A). Indeed, both these precultured cells lead to a cell dose-dependent suppression of the anti-TNP response when transferred at the initiation of antigen-stimulated fresh cell cultures. T cells are the effectors of both these suppressions and seem to directly suppress the B-cell response. We tested the in vitro effect of Az (10(-1) micrograms/ml) on the generation of these two sets of suppressors. Whereas that of Con-A-induced suppressors proves to be resistant, that of spontaneously-induced T suppressors is totally prevented by the addition of Az in the preculture medium. Instead, Az treatment allows the manifestation of a spontaneously-induced helper T cell, simultaneously generated, which is able to increase a T-independent antibody response and quite resistant to the in vitro effect of Az. Thus, this study demonstrates that different subpopulations of T lymphocytes regulating the B-cell antibody response exhibit a selectivity to Az, implying different cell proliferation requirements and/or different cellular origin.  相似文献   
4.
5.
1. In the present study, we developed an experimental model of cystitis induced by cyclophosphamide (CYP). In order to characterize des-Arg9-BK-induced contraction on the urinary bladder (UB) during the development of inflammation and to quantify kinin B1 receptor gene expression using a quantitative RT - PCR technique. 2. In the presence of peptidase inhibitors captopril (10 microM), DL-thiorphan (1 microM) and DL-2-mercaptomethyl-3-guanidino-ethylthiopropanoic acid (MERGEPTA 5 microM), bradykinin (BK) (0.3 - 3,000 nM) evoked a concentration-dependent contraction of rat UB which was not different between the CYP- and vehicle-treated groups. Unlike BK, des-Arg9-BK (0.3 - 100,000 nM) did not contract UB from vehicle-treated rats but contracted vigorously bladder strips from CYP-treated rats 14, 24 and 168 h after treatment. In UB of 24 h treated rat, the pD2 value of des-Arg9-BK was 7.3+/-0.1. 3. The cyclo-oxygenase inhibitor indomethacin (3 microM) reduced by 30% the maximal response of des-Arg9-BK. Both the kinin B1 receptor antagonists des-Arg9-[Leu8]BK (10 microM) and des-Arg10-Hoe 140 (10 microM) produced a rightward shift of the concentration-response curve to des-Arg9-BK yielding pKB values of 6.8+/-0.2 and 7.2+/-0.1, respectively, whilst the kinin B2 receptor antagonist Hoe 140 (1 microM) had no effect. 4. After CYP treatment, mRNA coding for the kinin B1 receptor appeared predominantly in UB. In this organ, the induction was progressive, reaching a maximum 48 h after CYP treatment. 5. In conclusion, the present study provides strong evidence for an induction of kinin B1 receptors in UB of CYP-treated rats. This was associated at a molecular level with an increase in mRNA expression of the gene coding for the kinin B1 receptor. This kinin receptor displayed the whole features of a classical rat kinin B1 receptor.  相似文献   
6.
We have reviewed 37 patients with scapholunate instability, operated in Paris between 1979 and 1995 7 months after the injury. There were 12 partial and 18 complete ligament ruptures, but also 4 distensions. The repair was a secondary suture in 16 cases (7 direct, 1 transosseous, 1 combined, 5 anchor, 2 transosseous with anchor). A capsulodesis was performed 7 times as an isolated and 8 times as a combined procedure. 6 previous cases have been treated by ligamentoplasty. We present the results after a mean postoperative follow-up of 27 months, with good results on pain and grip, maintaining a satisfactory range of motion.  相似文献   
7.
BACKGROUND: Unsafe delivery and overuse of injections can result in the spread of hepatitis B virus, hepatitis C virus, and HIV. The aim of the present survey was to estimate the frequency of safe injection practices in Burkina Faso. METHOD: Using the new standardized World Health Organization tool to assess injection practices, we selected 80 primary health facilities with a two-stage cluster sampling method, collected information using structured observations and provider interviews, and analyzed the data using Epi-Info software. RESULTS: We observed 116 injections in 52 facilities. In 50 facilities [96%; 95% confidence interval (CI) 85-99%] injections were given with a new, single-use syringe and needle. In 29 facilities (56%; 95% CI 36-74%), staff recapped needles using two hands. All 80 facilities visited had a stock in the community to provide new, single-use syringes and needles. In 61% (95% CI 54-79%) of facilities, staff reported needlestick injuries in the last 12 months. Used needles were discarded in open containers in 66 facilities (83%; 95% CI 55-96%) and observed in the surroundings of 46 facilities (57%; 95% CI 32-80%). CONCLUSIONS: In 2000, most of the health facilities in Burkina Faso were using sterile injection equipment. However, practices were still observed that could expose patients, health care workers, and communities to risks, and that required specific interventions.  相似文献   
8.
Neutropenic enterocolitis is a potentially fatal complication of myeloablative chemotherapy in patients with acute myeloid leukemia. Omega-3 polyunsaturated fatty acids (PUFA) are precursors of potent anti-inflammatory prostaglandins. Our aim was to explore the safety and effectiveness of omega-3 PUFA added to parenteral nutrition in protecting leukemia patients from severe enterocolitis. Fourteen patients with acute myeloid leukemia who received omega-3 PUFA in a Phase II trial were compared with 66 consecutive control patients not getting this intervention. We performed crude and adjusted comparisons, using inverse probability of treatment weighting for adjusted analysis, and blind outcome assessment to minimize assessor bias. Primary outcome was severe enterocolitis (≥Grade 3). The crude odds ratio of Grade 3 colitis or higher was 1.36 (95% CI 0.37 to 4.96, P = 0.64), and the adjusted odds ratio was 0.79 (95% CI 0.35 to 1.78, P = 0.57). There was little evidence to suggest differences between groups in serious adverse events and overall mortality. Our results provide little evidence that addition of omega-3 PUFA is beneficial in this condition. Routine treatment with omega-3 PUFA is currently not warranted.  相似文献   
9.
10.
The choledochus and pancreatic duct ordinarily enter the duodenum either separately or via a common channel located in the duodenal wall. The usual maximal length of the common channel is approximately 0.5 cm. An anomalous junction of the pancreaticobiliary tract is defined by the presence of an unusually long common channel whose length is 1 cm or longer. During the last 8 years, we studied 9 cases of congenital dilatation of the bile duct. Besides the choledochal cyst, all patients had a common channel which measured 1.5 cm or longer. The mean age of patients (6 females, 3 males) was 36.5 years. Three patients had extrahepatic bile tract carcinoma. One patient, a 51-year old man, had gallbladder carcinoma without stones while the two other patients, a 43-year old woman and a 32-year old man, had carcinoma arising from the wall of the cystic dilatation. These two patients had undergone a simple internal drainage procedure 16 and 8 years before, respectively. Our study suggests that the anomalous junction of the pancreaticobiliary tract, an embryonic anomaly which allows the reflux of pancreatic juice into the bile duct and gallbladder, may be responsible for congenital bile duct dilatation and biliary tract carcinoma. Total excision of the cystic dilatation and the gallbladder with hepaticojejunostomy is the appropriate surgical treatment.  相似文献   
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