Radiotherapy treatment planning is a multi-criteria problem. Any optimization of the process produces a set of mathematically optimal solutions. These optimal plans are considered mathematically ...equal, but they differ in terms of the trade-offs involved. Since the various objectives are conflicting, the choice of the best plan for treatment is dependent on the preferences of the radiation oncologists or the medical physicists (decision makers).
We defined a clinically relevant area on a prostate Pareto front which better represented clinical preferences and determined if there were differences among radiation oncologists and medical physicists.
Pareto fronts of five localized prostate cancer patients were used to analyze and visualize the trade-off between the rectum sparing and the PTV under-dosage. Clinical preferences were evaluated with Clinical Grading Analysis by asking nine radiation oncologists and ten medical physicists to rate pairs of plans presented side by side. A choice of the optimal plan on the Pareto front was made by all decision makers.
The plans in the central region of the Pareto front (1–4% PTV under-dosage) received the best evaluations. Radiation oncologists preferred the organ at risk (OAR) sparing region (2.5–4% PTV under-dosage) while medical physicists preferred better PTV coverage (1–2.5% PTV under-dosage). When the Pareto fronts were additionally presented to the decisions makers they systematically chose the plan in the trade-off region (0.5–1% PTV under-dosage).
We determined a specific region on the Pareto front preferred by the radiation oncologists and medical physicists and found a difference between them.
Background: Vascular endothelial growth factor (VEGF) expression may act as a sensitive measure of the angiogenic potential of a lesion. Furthermore, VEGF has been implicated in the pathogenesis of ...cystic tumors and inflammatory odontogenic cysts. Thus, we studied the expression of VEGF in the epithelium of odontogenic keratocyst (OK) in association with cell proliferation and apoptosis.
Methods: Forty‐two cases of OK, 26 cases of dentigerous cyst (DC), and 15 cases of residual cyst (RC) were retrospectively examined by immunohistochemistry for VEGF, Ki67/Mib‐1 and anti‐caspase‐3. For VEGF and caspase‐3, the intensity of immunostaining was qualitatively assessed, while for the evaluation of Ki67 the average number of positively stained nuclei in 10 high‐power microscopic fields (×400) was calculated.
Results: The VEGF expression was stronger in OK when compared with DC (P < 0.007). The rate of nuclear Ki67 expression in OK was significantly higher than that in DC (P < 0.001) and RC (P < 0.001). Cytoplasmic caspase‐3 expression was statistically more intense in RC than in OK (P = 0.001) or DC (P < 0.001). A statistically significant correlation was seen in OK for Ki67 (P < 0.001) and VEGF (P = 0.023), but not for caspase‐3. Multiple regression analysis revealed a linear relationship between VEGF and Ki67.
Conclusions: The VEGF was expressed in the epithelium of OK, DC, and RC with a variable intensity, and in OK VEGF expression was related to Ki67. It is suggested that VEGF expression by the odontogenic epithelium is not induced solely by inflammation.
Summary
Previous studies have shown that alpha1‐adrenergic receptor antagonists may alter seminal vesicle contractility and impair fertility in male rats. This study was designed to investigate the ...effects of terazosin on the catalase expression in the seminal vesicles and the lipid peroxidation of the seminal fluid in normal adult rats. Wistar rats were treated with terazosin (1.2 mg kg−1 body weight, given orally every second day) for 120 days. Catalase expression was assessed immunohistochemically in tissue sections of the seminal vesicles, and lipid peroxidation was estimated by measuring the malondialdehyde (MDA) levels in the seminal vesicles' fluid. The seminal vesicles in terazosin‐treated rats were particularly distended in comparison with those of controls, and their secreting epithelium was suppressed. Cytoplasmic catalase expression in the secreting epithelial cells (% of cells) was increased in terazosin‐treated specimens in comparison with controls (76.1 ± 17.1 versus 51.3 ± 25.1, P = 0.005). MDA levels (μm) were also higher in samples from treated subjects in comparison with controls (2.67 ± 1.19 versus 1.39 ± 0.19, P = 0.01). Although the direct effect of terazosin treatment on the seminal vesicles is that of impaired contractility, an indirect effect is that on fertility by increasing lipid peroxidation in the seminal fluid and/or through degrading of hydrogen peroxide that is essential for sperm capacitation.
ABSTRACT
Aim Vascular endothelial growth factor (VEGF) seems to be a critical molecule in cervical carcinogenesis. We aimed to investigate the possible associations between hormonal factors and VEGF ...expression in cervical epithelial cells from postmenopausal women.
Method A total of 105 healthy postmenopausal women (aged 45-68 years old) attending a university menopause clinic were enrolled in this cross-sectional study. Pap smears were derived from current users of 17β-estradiol 1 mg + norethisterone acetate 0.5 mg (n = 28), tibolone 2.5 mg (n = 23), raloxifene HCl 60 mg (n = 21) and women not receiving treatment (n = 33). VEGF immunostaining was evaluated in squamous, glandular and metaplastic cells, using a semiquantitative method (rating scale: 0-3).
Results Concerning endogenous hormones, higher Δ4-androstenedione levels were associated with more intense VEGF immunostaining in glandular (p = 0.041) and metaplastic cells (p = 0.004). Hormone therapy and raloxifene did not induce any changes in VEGF immunoreactivity in the examined cells. In contrast, tibolone administration was accompanied by diminished VEGF presence in metaplastic cells (p = 0.016 vs. controls).
Conclusion Our findings may in part reflect the molecular processes contributing to the safe profile of hormone therapy, tibolone and raloxifene in cervical carcinogenesis.
The aim of this study was to investigate the patterns of renal function recovery during partial nephrectomy (PN) on an experimental solitary kidney rabbit model and establish the upper tolerable time ...limits of applied ischemia. Forty-eight New Zealand rabbits underwent an open right nephrectomy and after 30 days, the animals were clustered into five groups (A, B, C, D, E). The first four groups received an open left PN, under different types of ischemia. Groups A (n = 8) and B (n = 10) were subjected to 90 and 60 min of warm ischemia (WI), respectively, while groups C (n = 10) and D (n = 10) received 90 and 120 min of cold ischemia (CI) with ice-slush cooling. Group E (n = 10) served as sham group. Serum determinations of creatinine (SCr) and BUN were recorded preoperatively and on postoperative days (POD) 1, 3, 6 and 15. The animals were euthanized and the remaining kidneys were harvested and evaluated microscopically. The type and duration of ischemia were statistically significant parameters (P < 0.001). Groups B, C and D exhibited a similar pattern of recovery from trial initiation to the 15th POD (P = 0.788 and P = 0.068, respectively). Group A was extremely differentiated, with 100% mortality caused by uremia. The microscopic findings were consistent to the serum biochemistry. In our solitary kidney rabbit model, the upper limits of tolerable WI seem to be set on 60 min. CI can safely preserve the model's renal function--even up to 120 min.
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