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61.
Reyes-Trejo B Sánchez-Mendoza ME Becerra-García AA Cedillo-Portugal E Castillo-Henkel C Arrieta J 《The Journal of pharmacy and pharmacology》2008,60(7):931-936
Croton reflexifolius H. B. K (Euphorbiaceae) is a very common medicinal plant in the Huastecan region of Mexico that, according to local folk medicine, is considered useful in the treatment of gastritis and gastric ulcer. We have aimed to test the validity of this practice by using the experimental model of an ethanol-induced gastric ulcer in male Wistar rats. The results showed that C. reflexifolius had gastroprotector activity, that the hexane extract had the highest protective activity (64.38+/-7.72%), and that polyalthic acid isolated from this extract was the main active gastroprotector agent. Rats treated orally with polyalthic acid showed a gastroprotective effect similar to that elicited by carbenoxolone. As with carbenoxolone, the effect elicited by polyalthic acid was attenuated by pretreatment with either N(G)-nitro-L-arginine methyl ester (70 mgkg(-1), i.p.), a nitric oxide (NO) synthase inhibitor, or N-ethylmaleimide (10 mgkg(-1), s.c.), a blocker of sulfhydryl groups. This suggested that the gastroprotective mechanism of this diterpenoid involved the participation of both NO and endogenous sulfhydryl groups. Contrary to carbenoxolone, the gastroprotective effect of polyalthic acid was not affected by the inhibition of prostaglandin synthesis with indometacin (10 mgkg(-1), s. c.). In conclusion, Croton reflexifolius contains compounds with gastroprotector activity. Polyalthic acid, which was isolated from this plant, was the main compound with gastroprotector activity, having effectiveness similar to that found with the use of carbenoxolone. Whereas NO and sulfhydryl groups were involved in the mechanisms of gastroprotective action of polyalthic acid, prostaglandins were not. 相似文献
62.
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64.
Ki67 Changes Identify Worse Outcomes in Residual Breast Cancer Tumors After Neoadjuvant Chemotherapy 下载免费PDF全文
65.
Nutritional Status,Body Surface,and Low Lean Body Mass/Body Mass Index Are Related to Dose Reduction and Severe Gastrointestinal Toxicity Induced by Afatinib in Patients With Non‐Small Cell Lung Cancer 下载免费PDF全文
Oscar Arrieta Martha De la Torre‐Vallejo Diego López‐Macías David Orta Jenny Turcott Eleazar‐Omar Macedo‐Pérez Karla Sánchez‐Lara Laura‐Alejandra Ramírez‐Tirado Vickie E. Baracos 《The oncologist》2015,20(8):967-974
Background.
The main reason for dose reduction of afatinib is gastrointestinal toxicity (GT). In a phase II study, we analyzed anthropometrical, nutritional, and biochemical factors associated with GT induced by afatinib.Materials and Methods.
Patients diagnosed with non-small cell lung cancer who progressed to prior chemotherapy received 40 mg of afatinib. Malnutrition was determined by Subjective Global Assessment, and lean body mass (LBM) was determined by computed tomography scan analysis using a pre-established Hounsfield unit threshold. Toxicity was obtained during four cycles by Common Terminology Criteria for Adverse Events.Results.
Eighty-four patients were enrolled. Afatinib was administered as the second, third, and fourth line of treatment in 54.8%, 38.1%, and 7.12% of patients, respectively. Severe diarrhea, mucositis, and overall severe GT were present in 38.9%, 28.8%, and 57.5%, respectively. Of the patients, 50% developed dose-limiting toxicity (DLT). Patients with malnutrition have higher risk for severe GT. Patients with lower LBM and body mass index developed more DLT (71.4% vs. 18.8%).Conclusion.
Malnutrition is associated with a higher risk of severe GT induced by afatinib. Determination of nutritional status and body composition are helpful in identifying patients at higher risk of severe GT and could allow initiating treatment with lower doses according to tolerance.Implications for Practice:
Body composition analysis, specifically lean body mass quantification, and nutritional status assessment are significant clinical variables to take into account when assessing oncological patients. This study on patients with non-small cell lung cancer treated with afatinib showed the important impact that malnutrition and low lean body mass have on the risk for developing dose-limiting toxicity and severe gastrointestinal toxicity. Still more research needs to be done to explore dose adjustment according to lean body mass, especially in drugs that are given at fixed doses, such as afatinib. However, this study presents evidence for the clinical oncologist to have a closer follow-up with malnourished patients and even to consider a lower starting dose until therapeutic dose is achieved. 相似文献66.
Patricia Guevara Elizabeth Escobar-Arriaga David Saavedra-Perez Abelardo Martinez-Rumayor Diana Flores-Estrada Daniel Rembao Alejandra Calderon Julio Sotelo Oscar Arrieta 《Journal of neuro-oncology》2010,98(3):379-384
Meningiomas are benign tumors, with low rate of recurrence after surgery. The most important factor predicting recurrence is the extent of surgical resection; other factors have been studied with conflicting results. Angiogenesis, an important substratum for growth and spread of neoplasic cells, and the expression of estrogen and progesterone receptors (ER, PR), could play a role in the recurrence of meningioma. We evaluated 42 patients with meningioma diagnosis (confirmed by histopathology) treated exclusively by surgery between January 1995 and December 1999, and compared the recurring and non-recurring groups after a ten-year follow-up period. Recurrence was associated with several factors including vascular density (VD), cell proliferation index (CPI), ER, PR, and cyclin E (CE) tissue expression, as evaluated by immunohistochemistry. Complete surgical resection was achieved in 41% of patients. Recurrence of meningioma was found in 17 patients (40%). Median ± standard deviation (SD) of recurrence time was 32 ± 5 months. When recurrence versus no recurrence was compared, mean ± SD of VD and CPI were 9 ± 3.6 and 607.6 ± 233 (40×/10 fields) respectively. Tissue expression was positive for ER, PR, and CE in 28, 62 and 91% of patients, respectively. The sole significant recurrence-associated factors were extent of resection (P = 0.003) and VD (P = 0.004). ER, PR, and CE-tissue expression were not statistically significant. The most important factor associated with meningioma relapse was vascular density, independently of hormonal status and extent of surgical resection. Patients with a high risk of recurrence could benefit from additional treatment. 相似文献
67.
K Kassir O Vargas-Shiraishi F Zaldivar M Berman J Singh A Arrieta 《Clinical and diagnostic laboratory immunology》2001,8(6):1060-1063
Urinary tract infections are common in infants and children. Pyelonephritis may result in serious complications, such as renal scarring, hypertension, and renal failure. Identification of the timing of release of inflammatory cytokines in relation to pyelonephritis and its treatment is essential for designing interventions that would minimize tissue damage. To this end, we measured urinary cytokine concentrations of interleukin-1 beta (IL-1 beta), IL-6, and IL-8 in infants and children with pyelonephritis and in healthy children. Children that presented to our institution with presumed urinary tract infection were given the diagnosis of pyelonephritis if they had a positive urine culture, pyuria, and one or more of the following indicators of systemic involvement: fever, elevated peripheral white blood cell count, or elevated C-reactive protein. Urine samples were obtained at the time of presentation prior to the administration of antibiotics, immediately after completion of the first dose of antibiotics, and at follow up 12 to 24 h after presentation. IL-1 beta, IL-6, and IL-8 concentrations were measured by enzyme-linked immunosorbent assay. Creatinine concentrations were also determined, and cytokine/creatinine ratios were calculated to standardize samples. Differences between pre-antibiotic and follow-up cytokine/creatinine ratios were significant for IL-1 beta, IL-6, and IL-8 (P < 0.01). Differences between pre-antibiotic and control cytokine/creatinine ratios were also significant for IL-1 beta, IL-6, and IL-8 (P < 0.01). Our study revealed that the urinary tract cytokine response to infection is intense but dissipates shortly after the initiation of antibiotic treatment. This suggests that renal damage due to inflammation begins early in infection, underscoring the need for rapid diagnosis and intervention. 相似文献
68.
Ivan Cordon María Jesús Nicolás Sandra Arrieta Manuel Alegre Julio Artieda Miguel Valencia 《Brain stimulation》2018,11(1):231-238
Background
High-frequency deep brain stimulation (DBS) has become a widespread therapy used in the treatment of Parkinson's Disease (PD) and other diseases. Although it has proved beneficial, much recent attention has been centered around the potential of new closed-loop DBS implementations.Objective
Here we present a new closed-loop DBS scheme based on the phase of the theta activity recorded from the motor cortex. By testing the implementation on freely moving 6-OHDA lesioned and control rats, we assessed the behavioral and neurophysiologic effects of this implementation and compared it against the classical high-frequency DBS.Results
Results show that both stimulation modalities produce significant and opposite changes on the movement and neurophysiological activity. Close-loop stimulation, far from improving the animals' behavior, exert contrary effects to those of high-frequency DBS which reverts the parkinsonian symptoms. Motor improvement during open-loop, high-frequency DBS was accompanied by a reduction in the amount of cortical beta oscillations while akinetic and disturbed behavior during close-loop stimulation coincided with an increase in the amplitude of beta activity.Conclusion
Cortical-phase-dependent close-loop stimulation of the STN exerts significant behavioral and oscillatory changes in the rat model of PD. Open-loop and close-loop stimulation outcomes differed dramatically, thus suggesting that the scheme of stimulation determines the output of the modulation even if the target structure is maintained. The current framework could be extended in future studies to identify the correct parameters that would provide a suitable control signal to the system. It may well be that with other stimulation parameters, this sort of DBS could be beneficial. 相似文献69.
Botella-Carretero JI Iglesias B Balsa JA Zamarrón I Arrieta F Vázquez C 《JPEN. Journal of parenteral and enteral nutrition》2008,32(2):120-128
BACKGROUND: Oral nutritional supplements have been recommended after orthopedic surgery in geriatric patients to reduce postoperative complications. However, tolerability of supplements could be a limitation, and their universal use is not supported by the heterogeneity of previous studies, especially in patients without malnutrition. METHODS: This study is a randomized, controlled, open, parallel, 3-arm clinical trial comparing supplementation with protein powder dissolved in liquids to aim at 36 g of protein per day, energy and protein supplements to aim at 37.6 g of protein and 500 kcal per day, or no intervention in normally nourished or mildly undernourished patients. Outcomes were serum albumin, prealbumin, retinol-binding globulin, and body mass index, among others. Postoperative complications were also recorded. RESULTS: Ninety patients aged 83.8 +/- 6.6 years were included. The mean ingested amount of supplements was 41.1% +/- 20.6% in the protein powder supplement group and 51.4% +/- 13.2% in the energy protein supplement group (t = 2.278, P = .027). Postoperative supplements had no effect on the nutrition status during in-hospital follow-up, as assessed by serum albumin (P = .251), prealbumin (P = .530), retinol-binding globulin (P = .552), or body mass index (P = .582). Multivariate analysis showed that length of hospital stay with an established complication until its resolution (beta = .230, P = .031), total hospital stay (beta = .450, P < .001), baseline body mass index (beta = .204, P = .045), and total daily ingested proteins per body weight (beta = .252, P = .018) were predictive variables on the change in serum albumin (R2 = 0.409, F = 11.246, P < .001). CONCLUSIONS: Oral nutritional supplements in normally nourished or only mildly undernourished geriatric patients with hip fracture submitted to surgery may be of interest for patients with postoperative complications and long hospital stays. 相似文献
70.
Andrés?F.?Cardona Oscar?Arrieta Martín?Ignacio?Zapata Leonardo?Rojas Beatriz?Wills Noemí?Reguart Niki?Karachaliou Hernán?Carranza Carlos?Vargas Jorge?Otero Pilar?Archila Claudio?Martín Luis?Corrales Mauricio?Cuello Carlos?Ortiz Luis?E.?Pino Rafael?Rosell Zyanya?Lucia?Zatarain-Barrón 《Targeted oncology》2017,12(4):513-523
Background
Lung cancer harboring epidermal growth factor receptor (EGFR) mutations and treated with EGFR tyrosine kinase inhibitors (TKIs) all eventually develop acquired resistance to the treatment, with half of the patients developing EGFR T790M resistance mutations.Objective
The purpose of this study was to assess histological and clinical characteristics and survival outcomes in Hispanic EGFR mutated lung cancer patients after disease progression.Patients and Methods
EGFR mutation-positive lung cancer patients (n = 34) with acquired resistance to the EGFR-TKI erlotinib were identified from 2011 to 2015. Post-progression tumor specimens were collected for molecular analysis. Post-progression interventions, response to treatment, and survival were assessed and compared among all patients and those with and without T790M mutations.Results
Mean age was 59.4 ± 13.9 years, 65% were never-smokers, and 53% had a performance status 0–1. All patients received erlotinib as first-line treatment. Identified mutations included: 60% DelE19 (Del746–750) and 40% L858R. First-line erlotinib overall response rate (ORR) was 61.8% and progression free survival (PFS) was 16.8 months (95% CI: 13.7–19.9). Acquired resistance mutations identified were T790M mutation (47.1%); PI3K mutations (14.7%); EGFR amplification (14.7%); KRAS mutation (5.9%); MET amplification (8.8%); HER2 alterations (5.9%, deletions/insertions in e20); and SCLC transformation (2.9%). Of patients, 79.4% received treatment after progression. ORR for post-erlotinib treatment was 47.1% (CR 2/PR 14) and median PFS was 8.3 months (95% CI: 2.2–36.6). Median overall survival (OS) from treatment initiation was 32.9 months (95% CI: 30.4–35.3), and only the use of post-progression therapy affected OS in a multivariate analysis (p = 0.05).Conclusions
Hispanic patients with acquired resistance to erlotinib continued to be sensitive to other treatments after progression. The proportion of T790M+ patients appears to be similar to that previously reported in Caucasians.