Purpose: To assess the toxicity, pathologic response rates, type of surgery, and oncologic results in a prospective Phase I-II trial using pure hyperfractionated radiotherapy (RT) preoperatively in locally advanced rectal cancer.
Methods And Materials: Between September 1997 and April 2000, 50 patients with T3-T4 or N1 rectal cancers were treated preoperatively with 50 Gy (45 Gy to the pelvis and a 5-Gy tumor boost) in 40 fractions of 1.25 Gy during 4 weeks. The pretreatment tumor stage as determined by CT and endorectal ultrasonography (80% of patients) included 1 Stage T2 (2%), 45 T3 (90%), and 4 T4 (8%). Nodal involvement (N1) was documented in 26 patients (52%). Surgery was performed at a median interval of 45 days (range 26-114 days) after RT completion. Seventeen patients who presented with pT4 or pN1 and/or pM1 received 5-fluorouracil-based chemotherapy postoperatively.
Results: All patients completed the RT schedule as planned. Severe acute toxicities included two Grade 3 skin reactions (4%) that did not require a break. The other acute toxicities were Grade 2 or less (skin, diarrhea, urinary, rectal tenesmus, and fatigue). A complete pathologic response was observed in 7 patients (14%), and microscopic residual cancer was found in 10 (20%). Of the 20 patients presenting with tumor located < or = 6 cm from the anal verge, sphincter-saving surgery was performed in 14 (70%). At 3 years, the actuarial locoregional control rate was 90.5%, and the disease-free survival rate was 74.6%. At a median follow-up of 32 months, 4 patients (8%) presented with severe late complications (Grade 3-4) that might have been RT related (one rectovaginal fistula, two chronic perineal fistulas, and one bilateral ureteral stenosis).
Conclusion: In locally advanced rectal cancer, preoperative hyperfractionated RT to a total dose of 50 Gy is feasible, with acceptable acute and late toxicity and an objective downstaging effect. In view of these results, this schedule might be used as a basis for additional investigation regarding RT dose escalation or the addition of concomitant chemotherapy.
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http://dx.doi.org/10.1016/s0360-3016(02)03003-1 | DOI Listing |
BMC Microbiol
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Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, Taizhou Key Laboratory of Biomedicine and Advanced Dosage Forms, School of Life Sciences, Taizhou University, Taizhou, 318000, Zhejiang Province, China.
The microbiota inhabiting the surface of fish mucosal tissue play important roles in the nutrition, metabolism and immune system of their host. However, most investigations on microbial symbionts have focused on the fish gut, but the microbiota associated with external mucosal tissues (such as the skin and gill) is poorly understood. This study characterised the traits and dynamic of microbial communities associated with the skin, gill and gut of large yellow croaker (Larimichthys crocea) culturing with net enclosures or pens at different sampling times (with seasonal transition).
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January 2025
Saint Petersburg State University, St. Petersburg, 198504, Russia.
Using angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT), an experimental and theoretical study of changes in the electronic structure (dispersion dependencies) and corresponding modification of the energy band gap at the Dirac point (DP) for topological insulator (TI) [Formula: see text] have been carried out with gradual replacement of magnetic Mn atoms by non-magnetic Ge atoms when concentration of the latter was varied from 10% to 75%. It was shown that when Ge concentration increases, the bulk band gap decreases and reaches zero plateau in the concentration range of 45-60% while trivial surface states (TrSS) are present and exhibit an energy splitting of 100 and 70 meV in different types of measurements. It was also shown that TSS disappear from the measured band dispersions at a Ge concentration of about 40%.
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January 2025
China Coal Shanxi China Resources Liansheng Energy Investment Co., LTD, Lvliang, 033000, China.
Bolt support improves the stress state of the surrounding rock and forms an integral bearing structure inside the anchored surrounding rock. Therefore, it is of theoretical significance and practical application value to systematically study the mechanical mechanism and bearing characteristics of the anchorage composite carrier and elucidate the interaction mechanism between the bearing effect of the anchorage composite carrier and the stability of the roadway surrounding rock. In this paper, a mechanical model for the anchorage composite carrier is meticulously constructed through a fusion of theoretical analysis and advanced numerical simulation techniques.
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January 2025
Jiangxi Tellhow Power Technology Co., Ltd, Nanchang, 330031, China.
This paper presents a surrogate-assisted global and distributed local collaborative optimization (SGDLCO) algorithm for expensive constrained optimization problems where two surrogate optimization phases are executed collaboratively at each generation. As the complexity of optimization problems and the cost of solutions increase in practical applications, how to efficiently solve expensive constrained optimization problems with limited computational resources has become an important area of research. Traditional optimization algorithms often struggle to balance the efficiency of global and local searches, especially when dealing with high-dimensional and complex constraint conditions.
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Department of Gastroenterology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China. Electronic address:
Colon cancer is a leading cause of cancer-related morbidity and mortality worldwide, necessitating advancements in therapeutic strategies to improve outcomes. Current treatment modalities, including surgery, chemotherapy, and radiation, are limited by systemic toxicity, low drug utilization rates, and off-target effects. Colon-targeted drug delivery systems (CDDS) offer a promising alternative by leveraging the colon's unique physiology, such as near-neutral pH and extended transit time, to achieve localized and controlled drug release.
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