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81.
M M Borner J Bernhard D Dietrich R Popescu M Wernli P Saletti D Rauch R Herrmann D Koeberle H Honegger P Brauchli D Lanz A D Roth 《Annals of oncology》2005,16(2):282-288
BACKGROUND: To determine the efficacy, impact on quality-of-life (QoL) and tolerability of two different irinotecan administration schedules in combination with capecitabine as first-line treatment of metastatic colorectal cancer. PATIENTS AND METHODS: We carried out a randomized phase II trial to select one of the following treatment regimens for further investigation: weekly irinotecan at a dose of 70 mg/m(2) days 1, 8, 15, 22, 29 (arm A) or 3-weekly irinotecan at a dose of 300/240 mg/m(2) day 1 and days 22 (arm B) in combination with capecitabine 1000 mg/m(2) twice daily days 1-14 and days 22-35 every 6 weeks. RESULTS: Seventy-five patients with good performance status entered the trial. The two arms were well balanced for relevant patient and disease characteristics. The most frequent toxic effects were grade 3/4 diarrhea (arm A: 34%, B: 19%), grade 3/4 neutropenia (A: 5%, B: 19%) and grade 2/3 alopecia (A: 26%, B: 65%). Other grade 3/4 toxic effects were rare (<5%). Response rates were 34% [95% confidence interval (CI) 20% to 51%] in arm A and 35% (95% CI: 20% to 53%) in arm B. Median time to progression was 6.9 (4.6-10.1) and 9.2 (7.9-11.5) months and median overall survival was 17.4 (12.6-23.0+) and 24.7 (16.3-26.4+) months. Patients with an objective tumor response reported better physical well-being (P < 0.01), mood (P < 0.05), functional performance (P < 0.05) and less effort to cope (P < 0.05) compared with the non-responders and stable disease patients. CONCLUSIONS: The primary end point of this study was the objective response rate and based on the statistical design of the trial, the 3-weekly irinotecan schedule was selected over weekly irinotecan administration. The 3-weekly irinotecan schedule also seemed advantageous in terms of grade 3/4 diarrhea, time to progression, overall survival and patient convenience, but the study was not designed to detect differences in these parameters. In addition, tumor response was shown to have a beneficial effect on QoL indicators. 相似文献
82.
Occurrence and elimination of cyanobacterial toxins in two Australian drinking water treatment plants. 总被引:3,自引:0,他引:3
In Australian freshwaters, Anabaena circinalis, Microcystis spp. and Cylindrospermopsis raciborskii are the dominant toxic cyanobacteria. Many of these surface waters are used as drinking water resources. Therefore, the National Health and Medical Research Council of Australia set a guideline for MC-LR toxicity equivalents of 1.3 microg/l drinking water. However, due to lack of adequate data, no guideline values for paralytic shellfish poisons (PSPs) (e.g. saxitoxins) or cylindrospermopsin (CYN) have been set. In this spot check, the concentration of microcystins (MCs), PSPs and CYN were determined by ADDA-ELISA, cPPA, HPLC-DAD and/or HPLC-MS/MS, respectively, in two water treatment plants in Queensland/Australia and compared to phytoplankton data collected by Queensland Health, Brisbane. Depending on the predominant cyanobacterial species in a bloom, concentrations of up to 8.0, 17.0 and 1.3 microg/l were found for MCs, PSPs and CYN, respectively. However, only traces (<1.0 microg/l) of these toxins were detected in final water (final product of the drinking water treatment plant) and tap water (household sample). Despite the low concentrations of toxins detected in drinking water, a further reduction of cyanobacterial toxins is recommended to guarantee public safety. 相似文献
83.
In skeletal muscle, insulin activates glycogen synthase by reducing phosphorylation at both NH2- and COOH-terminal sites of the enzyme and by elevating the levels of glucose-6-phosphate, an allosteric activator of glycogen synthase. To study the mechanism of regulation of glycogen synthase by insulin and glucose-6-phosphate, we generated stable Rat-1 fibroblast clones expressing rabbit muscle glycogen synthase with Ser-->Ala substitutions at key phosphorylation sites. We found that 1) elimination of the phosphorylation of either NH2- or COOH-terminal sites did not abolish insulin stimulation of glycogen synthase; 2) mutations at both Ser-7 and Ser-640 were necessary to bypass insulin activation; 3) mutation at Ser-7, coupled with the disruption of the motif for recognition by glycogen synthase kinase-3 (GSK-3), did not eliminate the insulin effect; and 4) mutation of either Ser-7 or Ser-640 increased the sensitivity of glycogen synthase to glucose 6-phosphate >10-fold. We conclude that Ser-7 and Ser-640 are both involved in mediating the response of glycogen synthase to insulin and activation by glucose 6-phosphate. In Rat-1 fibroblasts, GSK-3 action is not essential for glycogen synthase activation by insulin, and GSK-3-independent mechanisms also operate. 相似文献
84.
von Minckwitz G Darb-Esfahani S Loibl S Huober J Tesch H Solbach C Holms F Eidtmann H Dietrich K Just M Clemens MR Hanusch C Schrader I Henschen S Hoffmann G Tiemann K Diebold K Untch M Denkert C 《Breast cancer research and treatment》2012,132(3):863-870
Adjacent ductal carcinoma in situ (DCIS) is found in approximately 45% of invasive ductal carcinomas (IDC) of the breast. Pure DCIS overexpresses HER2 in approximately 45%. There is uncertainty whether adjacent DCIS impacts on the response to neoadjuvant chemotherapy and trastuzumab as well as whether HER2 expression in IDC component or adjacent DCIS changes throughout treatment. Core biopsies and surgical tissue from participants of the GeparQuattro study with HER2-positive IDC were centrally examined for the area of invasive ductal component and adjacent DCIS before and after receiving neoadjuvant anthracycline?Ctaxane?Ctrastuzumab containing chemotherapy. HER2 overexpression in IDC and adjacent DCIS was quantified separately by immunohistochemistry using the Ventana? automated staining system. Pathological complete response (pCR) was defined as no residual invasive or non-invasive tumor tissue. Fifty-nine (37.3%) of 158 IDCs presented with adjacent DCIS at diagnosis. These tumors showed lower regression grades than pure IDC (P?=?0.033). The presence of adjacent DCIS was an independent negative predictor of pCR [odds ratio 0.42 (95% CI 0.2?C0.9), P?=?0.027]. Adjacent DCIS area decreased from pre-treatment to surgery (r?=?0.205) with 30 (50.8%) IDCs with adjacent DCIS showing complete eradication of adjacent DCIS. HER2 status of adjacent DCIS was highly correlated with HER2 status of IDC component before (r?=?0.892) and after treatment (r?=?0.676). Degree of HER2 overexpression of the IDC component decreased in 16 (33.3%) out of 49 patients without a pCR. These 16 IDCs showed lower RGs compared to the 33 IDCs with unchanged HER2 expression (P?=?0.055). HER2-positive IDCs with adjacent DCIS is less responsive to neoadjuvant chemotherapy and trastuzumab compared to pure IDC. However, complete eradication of adjacent DCIS is frequently observed. HER2-overexpression of the invasive ductal component decreases in a subset of tumors, which showed less tumor regression. 相似文献
85.
Krenn L Presser A Pradhan R Bahr B Paper DH Mayer KK Kopp B 《Journal of natural products》2003,66(8):1107-1109
A sulfated emodin glucoside, emodin 8-O-beta-D-glucopyranosyl-6-O-sulfate (1), was isolated from the roots of Rheum emodi in an investigation of the active constituents of this Nepalese medicinal plant, and its structure was determined by spectroscopic and chemical methods. Additionally, two rare auronols, carpusin (2) and maesopsin (3), besides other anthraquinones and phenolics, were isolated and identified. Compounds 2 and 3 showed significant antioxidant activity in the DPPH assay, while chrysophanol, physcion, and emodin and their 8-O-glucosides were found to be inactive. 相似文献
86.
M L Dietrich T F Dolnicek W F Rayburn 《American journal of obstetrics and gynecology》1987,156(6):1403-1408
This prospective investigation was undertaken to compare the value of routine versus selective diabetes screening in a group of predominantly middle-class, healthy, Caucasian pregnant women. Two thousand consecutively chosen persons were divided into two groups: those to undergo routine screening between 24 and 28 weeks' gestation and those to be tested selectively in the presence of standard risk factors. The two groups of patients were otherwise similar. The method of screening involved a 50 gm oral glucose challenge, followed by a 3-hour glucose test if necessary. The incidence of gestational onset diabetes in the selectively screened group (19/453, 4.2%) was twice that in the routinely screened group (21/1000, 2.1%). Evidence of glucose intolerance without a risk factor was found in only one case (1/1000, 0.1%) in the routinely screened group. This assessment of our clinical practice has allowed us to safely eliminate the need for diabetes screening in more than half of our private patients, which will reduce office time, patient inconvenience, and expense. 相似文献
87.
TRPC6 is a Ca(2+)-permeable non-selective cation channel expressed in brain, smooth muscle containing tissues and kidney, as well as in immune and blood cells. Channel homomers heterologously expressed have a characteristic doubly rectifying current-voltage relationship and are six times more permeable for Ca2+ than for Na+. In smooth muscle tissues, however, Na+ influx and activation of voltage-gated calcium channels by membrane depolarization rather than Ca2+ elevation by TRPC6 channels is the driving force for contraction. TRPC6 channels are directly activated by the second messenger diacylglycerol (DAG) and regulated by specific tyrosine or serine phosphorylation. Extracellular Ca2+ has inhibitory effects, while Ca2+/calmodulin acting from the intracellular side has potentiator effects on channel activity. Given its specific expression, TRPC6 is likely to play a number of physiological roles. Studies with TRPC6(-/-) mice suggest a role for the channel in the regulation of vascular and pulmonary smooth muscle contraction. TRPC6 was identified as an essential component of the slit diaphragm architecture of kidney podocytes. Other functions in immune and blood cells, as well as in brain and in smooth muscle-containing tissues such as stomach, colon and myometrium, remain elusive. 相似文献
88.
89.
David W. McCormick Sara L. Rassoulian-Barrett Daniel R. Hoogestraat Stephen J. Salipante Dhruba SenGupta Elizabeth A. Dietrich Brad T. Cookson Grace E. Marx Joshua A. Lieberman 《Emerging infectious diseases》2023,29(3):467
Molecular methods can enable rapid identification of Bartonella spp. infections, which are difficult to diagnose by using culture or serology. We analyzed clinical test results of PCR that targeted bacterial 16S rRNA hypervariable V1–V2 regions only or in parallel with PCR of Bartonella-specific ribC gene. We identified 430 clinical specimens infected with Bartonella spp. from 420 patients in the United States. Median patient age was 37 (range 1–79) years; 62% were male. We identified B. henselae in 77%, B. quintana in 13%, B. clarridgeiae in 1%, B. vinsonii in 1%, and B. washoensis in 1% of specimens. B. quintana was detected in 83% of cardiac specimens; B. henselae was detected in 34% of lymph node specimens. We detected novel or uncommon Bartonella spp. in 9 patients. Molecular diagnostic testing can identify Bartonella spp. infections, including uncommon and undescribed species, and might be particularly useful for patients who have culture-negative endocarditis or lymphadenitis. 相似文献
90.
M Burkhardt U Nienaber A Pizanis M Maegele U Culemann B Bouillon S Flohe T Pohlemann T Paffrath T Dgu GP Dgu 《Critical care (London, England)》2012,16(4):R163
ABSTRACT: INTRODUCTION: Data on pre-hospital and trauma room fluid management of multiple trauma patients with pelvic disruptions are rarely reported. Present trauma algorithms recommend early haemorrhage control and massive fluid resuscitation. By matching the German Pelvic Injury Register (PIR) with the TraumaRegister DGU(R) (TR) for the first time, we attempt to assess the initial fluid management for different Tile/OTA types of pelvic ring fractures. Special attention was given to the patient's post traumatic course, particularly ICU data and patient outcome. METHODS: A specific match code was applied to identify certain patients with pelvic disruptions from both PIR and TR anonymous trauma databases, admitted between 2004 and 2009. From the resulting intersection set, a retrospective analysis was done of pre-hospital and trauma room data, length of ICU stay, days of ventilation, incidence of multiple organ dysfunction syndrome (MODS), sepsis, and mortality. RESULTS: In total 402 patients were identified. Mean ISS was 25.9 points and the mean ratio of patients with ISS [greater than or equal to]16 was 85.6%. The fracture distribution was as follows: 19.7% type A, 29.4% type B, 36.6% type C, and 14.3% isolated acetabular and/or sacrum fractures. The type B/C, compared with type A fractures, were related to constantly worse vital signs that necessitated a higher volume of fluid and blood administration in the pre-hospital and/or the trauma room setting. This group of B/C fractures were also related to a significantly higher presence of concomitant injuries and related with increased ISS. This was related to increased ventilation and ICU stay, increased rate of MODS, sepsis and increased rate of mortality at least for the type C fractures. Approximately 80% of the deceased had sustained type B/C fractures. CONCLUSIONS: The present study confirms the actuality of traditional trauma algorithms with initial massive fluid resuscitation in the recent therapy of multiple trauma patients with pelvic disruptions. Low volume resuscitation seems not yet accepted in practice in managing this special patient entity. Mechanically unstable pelvic ring fractures type B/C (according Tile's/OTA classification) form a distinct entity that has to be considered notably in future trauma algorithms. 相似文献