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951.
Melissa Pilewskie MD Cristina Olcese BS Anne Eaton MS Sujata Patil PhD Elizabeth Morris MD Monica Morrow MD Kimberly J. Van Zee MS MD 《Annals of surgical oncology》2014,21(5):1552-1560
Introduction
For women with ductal carcinoma in situ (DCIS) undergoing breast-conserving surgery (BCS), the benefit of magnetic resonance imaging (MRI) remains unknown. Here we examine the relationship of MRI and locoregional recurrence (LRR) and contralateral breast cancer (CBC) for DCIS treated with BCS, with and without radiotherapy (RT).Methods
A total of 2,321 women underwent BCS for DCIS from 1997 to 2010. All underwent mammography, and 596 (26 %) also underwent perioperative MRI; 904 women (39 %) did not receive RT, and 1,391 (61 %) did. Median follow-up was 59 months, and 548 women were followed for ≥8 years. The relationship between MRI and LRR was examined using multivariable analysis.Results
There were 184 LRR events; 5- and 8-year LRR rates were 8.5 and 14.6 % (MRI), respectively, and 7.2 and 10.2 % (no-MRI), respectively (p = 0.52). LRR was significantly associated with age, menopausal status, margin status, RT, and endocrine therapy. After controlling for these variables and family history, presentation, number of excisions, and time period of surgery, there remained no trend toward association of MRI and lower LRR [hazard ratio (HR) 1.18, 95 % confidence interval (CI) 0.79–1.78, p = 0.42]. Restriction of analysis to the no-RT subgroup showed no association of MRI with lower LRR rates (HR 1.36, 95 % CI 0.78–2.39, p = 0.28). No difference in 5- or 8-year rates of CBC was seen between the MRI (3.5 and 3.5 %) and no-MRI (3.5 and 5.1 %) groups (p = 0.86).Conclusions
We observed no association between perioperative MRI and lower LRR or CBC rates in patients with DCIS, with or without RT. In the absence of evidence that MRI improves outcomes, the routine perioperative use of MRI for DCIS should be questioned. 相似文献952.
Andrew X. Zhu MD Darrell R. Borger MD Yuhree Kim MD David Cosgrove MD Aslam Ejaz MD Sorin Alexandrescu MD Ryan Thomas Groeschl MD Vikram Deshpande MD James M. Lindberg MD Cristina Ferrone MD Christine Sempoux MD Thomas Yau MD Ronnie Poon MD Irinel Popescu MD Todd W. Bauer MD T. Clark Gamblin MD Jean Francois Gigot MD Robert A. Anders MD Timothy M. Pawlik MD MPH PhD 《Annals of surgical oncology》2014,21(12):3827-3834
Background
The molecular alterations that drive tumorigenesis in intrahepatic cholangiocarcinoma (ICC) remain poorly defined. We sought to determine the incidence and prognostic significance of mutations associated with ICC among patients undergoing surgical resection.Methods
Multiplexed mutational profiling was performed using nucleic acids that were extracted from 200 resected ICC tumor specimens from 7 centers. The frequency of mutations was ascertained and the effect on outcome was determined.Results
The majority of patients (61.5 %) had no genetic mutation identified. Among the 77 patients (38.5 %) with a genetic mutation, only a small number of gene mutations were identified with a frequency of >5 %: IDH1 (15.5 %) and KRAS (8.6 %). Other genetic mutations were identified in very low frequency: BRAF (4.9 %), IDH2 (4.5 %), PIK3CA (4.3 %), NRAS (3.1 %), TP53 (2.5 %), MAP2K1 (1.9 %), CTNNB1 (0.6 %), and PTEN (0.6 %). Among patients with an IDH1-mutant tumor, approximately 7 % were associated with a concurrent PIK3CA gene mutation or a mutation in MAP2K1 (4 %). No concurrent mutations in IDH1 and KRAS were noted. Compared with ICC tumors that had no identified mutation, IDH1-mutant tumors were more often bilateral (odds ratio 2.75), while KRAS-mutant tumors were more likely to be associated with R1 margin (odds ratio 6.51) (both P < 0.05). Although clinicopathological features such as tumor number and nodal status were associated with survival, no specific mutation was associated with prognosis.Conclusions
Most somatic mutations in resected ICC tissue are found at low frequency, supporting a need for broad-based mutational profiling in these patients. IDH1 and KRAS were the most common mutations noted. Although certain mutations were associated with ICC clinicopathological features, mutational status did not seemingly affect long-term prognosis. 相似文献953.
Renato Salvador Mario Costantini Francesco Cavallin Lisa Zanatta Elena Finotti Cristina Longo Loredana Nicoletti Giovanni Capovilla Romeo Bardini Giovanni Zaninotto 《Journal of gastrointestinal surgery》2014,18(1):106-112
Introduction
Laparoscopic Heller-Dor surgery is the current treatment of choice for patients with esophageal achalasia, but elderly patients are generally referred for less invasive treatments (pneumatic dilations or botulinum toxin injections).Aim
To assess the effect of age on the surgical outcome of patients receiving laparoscopic Heller-Dor as primary treatment.Methods
Demographic and clinical findings were prospectively collected on patients undergoing laparoscopic Heller-Dor from 1992 to 2012. Patients were classified in three age brackets: group A (≤45 years), group B (45–70), and group C (≥70). Treatment was defined as a failure if the postoperative symptom score was >10th percentile of the preoperative score (i.e., >8). We consecutively performed the Heller-Dor in 571 achalasia patients, 305 (53.4 %) in group A, 226 (39.6 %) in group B, and 40 (7 %) in group C.Results
The mortality was nil; the conversion and morbidity rates were both 1.1 %. Group C patients had higher preoperative symptom scores (p?=?0.02), while the symptom duration was similar in all three groups. Mucosal tears occurred in 17 patients (3 %): 6 (2 %) in group A, 8 (3.5 %) in group B, and 3 (7.5 %) in group C (p?=?0.09). The postoperative hospital stay was slightly longer for group C (p?=?0.06).Discussion
The treatment failure rate was quite similar: 31 failures in group A (10.1 %), 19 in group B (8.4 %), and 3 in group C (7.5 %; p?=?0.80). These failures were seen more in manometric pattern III (22.2 %, p?=?0.002). Laparoscopic Heller-Dor can be used as the first therapeutic approach to achalasia even in elderly patients with an acceptable surgical risk. 相似文献954.
Manuel Mateo-March Eneko Fernández-Pe?a Cristina Blasco-Lafarga Jaime Morente-Sánchez Mikel Zabala 《Journal of Sports Science and Medicine》2014,13(1):97-104
Maximising power output during the initial acceleration phase of a bicycle motocross (BMX) race increases the chance to lead the group for the rest of the race. The purpose of this study was to investigate the effect of non-circular chainrings (Q-ring) on performance during the initial acceleration phase of a BMX race. Sixteen male cyclists (Spanish National BMX team) performed two counterbalanced and randomized initial sprints (3.95s), using Q- ring vs. circular chainring, on a BMX track. The sample was divided into two different groups according to their performance (Elite; n = 8 vs. Cadet; n = 8). Elite group covered a greater distance using Q-ring (+0.26 m, p = 0.02; D = 0.23), whilst the improvement for the Cadet (+0.04 m) was not significant (p = 0.87; D = -0.02). Also, there was no significant difference in power output for the Elite group, while the Cadet group revealed larger peak power with the circular chainring. Neither lactate level, nor heart rate showed significant differences due to the different chainring used. The non-circular chainring improved the initial acceleration capacity only in the Elite riders.
Key Points
- This work provides novel results demonstrating very significant improvements in the sprint performance of BMX cycling discipline using a non-circular chainring system.
- This study seeks a practical application from scientific analysis
- All data are obtained in a real context of high competition using a sample comprised by the National Spanish Team.
- Some variables influencing performance as subjects’ physical fitness are discussed.
- Technical equipment approved by International Cycling Union is studied to check its potentially beneficial influence on performance.
955.
956.
Emily Brede Tom G. Mayer Whitney E. Worzer Maile Shea Cristina Garcia Robert J. Gatchel 《The spine journal》2014,14(8):1686-1693
Background contextFor chronic pain patients, recovery may be slowed by indecisiveness over optional surgery. These patients may be delayed from participating in interdisciplinary functional restoration (FR), pending resolution of the surgical decision. Uncertainty about surgery or rehabilitation leads to delayed recovery. A surgical option process (SOP) was developed to permit patients with chronic disabling occupational musculoskeletal disorders to enter FR, make a final determination halfway through treatment, and return to complete rehabilitation after surgery, if surgery was elected.PurposeThis study assessed the frequency with which an FR program can resolve an uncertain surgical option. It also assessed program completion rate and 1-year post-program outcomes for subgroups that decline surgery, request and receive surgery, or request surgery but are denied by surgeon or insurance carrier.Study designRetrospective study of a consecutive cohort.Patient sampleA cohort of 44 consecutively treated chronic disabling occupational musculoskeletal disorder patients were admitted to an FR program and identified as candidates for a surgical procedure but were either ambivalent about undergoing surgery, had a difference of opinion by two or more surgeons, or were denied a surgical request by an insurance carrier. Patients attended half (10 full day visits) of an FR program before making their own final determination to pursue a request or decline surgery.Outcome measuresPatients were assessed on surgical requests and whether surgery was ultimately performed, program completion status after the surgical determination, demographic variables, and 1-year outcomes on work status, additional surgery, and other health utilization measures.MethodsPatients became part of the SOP on program entry and were included in the study if they participated in a surgical-decision interview halfway through the program. Those who elected to decline surgery (DS) completed the program without delay, but those requesting surgery were placed on hold from the program while consultation and preauthorization steps took place. Those requesting surgery, but denied (RSD), and those undergoing surgery (US) were given the opportunity to complete FR following postoperative physical therapy or resolution of the surgical re-evaluation process.ResultsThere were 32 DS patients (73%), indicating that a large majority of patients declined the surgery that was still being considered when offered participation in the SOP. Of the 12 patients wanting a surgery, there were four US patients who received surgery previously denied (9% of cohort), and eight RSD patients (18% of cohort). Patients from the DS group completed the FR program at an 88% rate, as did 75% of US patients. However, despite an opportunity to re-enter and complete rehab, only 50% of RSD patients completed the FR option. Overall, patients who persistently sought surgery, contrary to the recommendations of a surgeon, had poorer outcomes. These 1-year post-FR outcomes included lower return-to-work and work retention rates, with higher rates of treatment seeking from new providers (resulting in higher rates of post-discharge surgery) and higher rates of recurrent injury claims after work return.ConclusionsA SOP tied to participation in an interdisciplinary FR program resolves uncertainty regarding surgical options in a high proportion of cases, resulting in a large majority declining surgery and completing the FR program. Timely surgery is also promoted decisively when needed. Findings suggest that patients who persistently seek surgery, contrary to the recommendations of a surgeon, frequently fail to complete FR and have poorer outcomes overall. 相似文献
957.
Josep Antoni Ramos-Quiroga Margarida Corominas-Roso Gloria Palomar Nuria Gomez-Barros Marta Ribases Cristina Sanchez-Mora Rosa Bosch Mariana Nogueira Montserrat Corrales Sergi Valero Miguel Casas 《Psychopharmacology》2014,231(7):1389-1395
Rationale
Atomoxetine (ATX) is a non-stimulant drug approved for the treatment of attention deficit hyperactivity disorder (ADHD). Although animal models have provided evidence that brain-derived neurotrophic factor (BDNF) is involved in the effects of ATX in the brain, there are no studies of BDNF in ADHD patients undergoing treatment with ATX.Objectives
The aim of this study was to evaluate the possible changes in serum levels of BDNF in adults treated with ATX and its relationship with clinical improvement.Methods
A total of 54 adults with ADHD (age 33.43?±?8.99 years) without any medical or psychiatric comorbidities were treated with ATX for 3 months; 35 of them completed the protocol. The clinical data for ADHD diagnosis, including Conners’ ADHD Rating Scale and blood samples, were collected at baseline (V1) and at the end of the treatment (V2).Results
Adults with ADHD who completed ATX treatment for 3 months showed a significant improvement in their clinical symptoms. No significant differences were found in BDNF levels before and after treatment with ATX in the whole group of patients (p?=?0.15). The inattentive subgroup of ATX responders showed a decrease of serum BDNF after 3 months of ATX treatment (p?=?0.05) not present in the combined subtype (p?=?0.82).Conclusions
These results suggest that BDNF is not directly involved in the neurobiological mechanisms of ATX-induced improvement of clinical symptoms of ADHD. The differences between the combined and inattentive subtypes in serum BDNF changes suggest selective ATX-induced effects in the function of brain circuitry. 相似文献958.
Alexandru Mihai Grumezescu Cristina Daniela Ghitulica Georgeta Voicu Keng-Shiang Huang Chih-Hui Yang Anton Ficai Bogdan Stefan Vasile Valentina Grumezescu Coralia Bleotu Mariana Carmen Chifiriuc 《International journal of pharmaceutics》2014
In this paper, we report the synthesis, characterization (FT-IR, XRD, BET, HR-TEM) and bioevaluation of a novel γ-aminobutiric acid/silica (noted GABA-SiO2 or γ-SiO2) hybrid nanostructure, for the improved release of topical antibiotics, used in the treatment of Staphylococcus aureus infections. GABA-SiO2 showed IR bands which were assigned to Si–O–Si (stretch mode). The XRD pattern showed a broad peak in the range of 18–30° (2θ), indicating an amorphous structure. Based on the BET analysis, estimations about surface area (438.14 m2/g) and pore diameters (4.76 nm) were done. TEM observation reveals that the prepared structure presented homogeneity and an average size of particles not exceeding 10 nm. The prepared nanostructure has significantly improved the anti-staphylococcal activity of bacitracin and kanamycin sulfate, as demonstrated by the drastic decrease of the minimal inhibitory concentration of the respective antibiotics loaded in the GABA-SiO2 nanostructure. These results, correlated with the high biocompatibility of this porous structure, are highlighting the possibility of using this carrier for the local delivery of the antimicrobial substances in lower active doses, thus reducing their cytotoxicity and side-effects. 相似文献
959.
Synthesis and In Vitro Pharmacological Evaluation of Novel 2‐Hydroxypropyl‐4‐arylpiperazine Derivatives as Serotoninergic Ligands
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960.
Christopher Salvo Ernesto Chicardi Rosalía Poyato Cristina García-Garrido Jos Antonio Jimnez Cristina Lpez-Pernía Pablo Tobosque Ramalinga Viswanathan Mangalaraja 《Materials》2021,14(9)
MAX phases are an advanced class of ceramics based on ternary carbides or nitrides that combine some of the ceramic and metallic properties, which make them potential candidate materials for many engineering applications under severe conditions. The present work reports the successful synthesis of nearly single bulk Ti2AlN MAX phase (>98% purity) through solid-state reaction and from a Ti and AlN powder mixture in a molar ratio of 2:1 as starting materials. The mixture of Ti and AlN powders was subjected to reactive spark plasma sintering (SPS) under 30 MPa at 1200 °C and 1300 °C for 10 min in a vacuum atmosphere. It was found that the massive formation of Al2O3 particles at the grain boundaries during sintering inhibits the development of the Ti2AlN MAX phase in the outer zone of the samples. The effect of sintering temperature on the microstructure and mechanical properties of the Ti2AlN MAX phase was investigated and discussed. 相似文献