213 research outputs found
Three-body Interactions Improve the Prediction of Rate and Mechanism in Protein Folding Models
Here we study the effects of many-body interactions on rate and mechanism in
protein folding, using the results of molecular dynamics simulations on
numerous coarse-grained C-alpha-model single-domain proteins. After adding
three-body interactions explicitly as a perturbation to a Go-like Hamiltonian
with native pair-wise interactions only, we have found 1) a significantly
increased correlation with experimental phi-values and folding rates, 2) a
stronger correlation of folding rate with contact order, matching the
experimental range in rates when the fraction of three-body energy in the
native state is ~ 20%, and 3) a considerably larger amount of 3-body energy
present in Chymotripsin inhibitor than other proteins studied.Comment: 9 pages, 2 tables and 5 figure
Redesigning and teaching veterinary microbiology laboratory exercises with combined on-site and online participation during the COVID-19 pandemic
The COVID-19 (coronavirus disease 2019) pandemic has forced universities to find new ways to conduct learning and teaching, as traditional face-to-face teaching has been prevented or restricted to an absolute minimum in many instances. Therefore, we redesigned and taught second-year veterinary student microbiology laboratory exercises (labs) with a hybrid learning approach. For this, a novel 'remote partner' model was implemented in which students present on-site in the laboratory worked synchronously pairwise with their remote partner present online. A student feedback survey revealed that in this remote partner model, both on-site and online participation in the labs were experienced as being useful in improving their laboratory skills. The students' overall performance in hands-on microbiological laboratory skills and safe working practices was similar in the hybrid learning approach (the 2021 class) and in the traditional on-site participation approach (the 2018-20 classes). This study suggests that the remote partner model is an effective way to acquire microbiological laboratory skills. This learning approach can be used in the non-pandemic future and/or also be applied to other fields.Microbiological laboratory skills can be developed using a hybrid model combining synchronous on-site and online learning for students working in pairs.Peer reviewe
Predictors of progression free survival, overall survival and early cessation of chemotherapy in women with potentially platinum sensitive (PPS) recurrent ovarian cancer (ROC) starting third or subsequent line(> 3) chemotherapy – the GCIG Symptom Benefit Study (SBS)
Background:
Potentially platinum sensitive recurrent ovarian cancer (PPS ROC) is defined by a platinum-free interval of >6 months, and usually treated with platinum-based chemotherapy with variable response and benefit in women who have had 3 or more lines of chemotherapy(≥3). We identified baseline characteristics (health-related quality of life[HRQL] and clinicopathological factors), associated with PFS, OS and early progression (within 8 weeks). The goal is to improve patient selection for chemotherapy based on a nomogram predicting PFS.
Methods:
HRQL was assessed with EORTC QLQ-C30/QLQ-OV28. Associations with PFS and OS were assessed with Cox proportional hazards regression. Variables significant in univariable analysis were included in multivariable analyses using backward elimination to select those significant. Associations with stopping chemotherapy early were assessed with logistic regression.
Results:
378 women were enrolled, with median(m)OS and PFS of 16.6 months and 5.3 months, respectively. The majority had ECOGPS 0–1. Chemotherapy was stopped early in 45/378 participants (12%); with mOS 3.4 months (95% CI: 1.7–7.2). Physical function(PF), role function(RF), cognitive function(CF), social function(SF), Global Health Status(GHS) and abdominal/GI symptoms(AGIS) were significant univariable predictors of PFS(p < 0.030). SF remained significant after adjusting for clinicopathological factors; p = 0.03. PF, RF, CF, SF, GHS and AGIS were significant univariable predictors of OS (p < 0.007); PF, RF, SF and GHS remained significant predictors of OS in multivariable models; p < 0.007. Poor baseline PF and GHS were significant univariable predictors of stopping chemotherapy early (p < 0.007) but neither remained significant after adjusting for clinicopathological factors.
Conclusion:
Baseline HRQL is simple to measure, is predictive of PFS and OS and when used in conjunction with clinicopathological prognostic factors, can assist with clinical decision making and treatment recommendations for women with PPSROC≥3
Hidden in plain sight - Survival consequences of baseline symptom burden in women with recurrent ovarian cancer
OBJECTIVE: To describe the baseline symptom burden(SB) experienced by patients(pts) with recurrent ovarian cancer(ROC) prior and associations with progression free survival (PFS) and overall survival (OS). METHODS: We analysed baseline SB reported by pts. with platinum resistant/refractory ROC (PRR-ROC) or potentially‑platinum sensitive ROC receiving their third or greater line of chemotherapy (PPS-ROC≥3) enrolled in the Gynecologic Cancer InterGroup - Symptom Benefit Study (GCIG-SBS) using the Measure of Ovarian Symptoms and Treatment concerns (MOST). The severity of baseline symptoms was correlated with PFS and OS. RESULTS: The 948 pts. reported substantial baseline SB. Almost 80% reported mild to severe pain, and 75% abdominal symptoms. Shortness of breath was reported by 60% and 90% reported fatigue. About 50% reported moderate to severe anxiety, and 35% moderate to severe depression. Most (89%) reported 1 or more symptoms as moderate or severe, 59% scored 6 or more symptoms moderate or severe, and 46% scored 9 or more symptoms as moderate or severe. Higher SB was associated with significantly shortened PFS and OS; five symptoms had OS hazard ratios larger than 2 for both moderate and severe symptom cut-offs (trouble eating, vomiting, indigestion, loss of appetite, and nausea; p < 0.001). CONCLUSION: Pts with ROC reported high SB prior to starting palliative chemotherapy, similar among PRR-ROC and PPS-ROC≥3. High SB was strongly associated with early progression and death. SB should be actively managed and used to stratify patients in clinical trials. Clinical trials should measure and report symptom burden and the impact of treatment on symptom control
Phase II biomarker trial of a multimarker diagnostic for ovarian cancer
The primary hypothesis to be tested in this study was that the diagnostic performance (as assessed by the area under the receiver operator characteristic curve, AUC) of a multianalyte panel to correctly identify women with ovarian cancer was significantly greater than that for CA-125 alone
Measuring what matters MOST: Validation of the Measure of Ovarian Symptoms and Treatment, a patient-reported outcome measure of symptom burden and impact of chemotherapy in recurrent ovarian cancer (ROC)
Purpose:
Gynecologic Cancer Intergroup Symptom Benefit Study (GCIG-SBS) Stage 2 aimed to review, revise, and validate a patient-reported outcome measure (PROM), the Measure of Ovarian Symptoms and Treatment concerns (MOST), developed in GCIG-SBS Stage 1 (MOSTv1, 35 items), and document recurrent ovarian cancer (ROC) symptom burden and benefit.
Methods:
GCIG-SBS Stage 2 recruited patients with platinum-resistant/refractory ROC (PRR-ROC) or potentially platinum-sensitive ROC with ≥ 3 lines of prior chemotherapy (PPS-ROC ≥ 3). Patients completed MOSTv1, QLQ-C30, QLQ-OV28, and FACT-O/FOSI at baseline and before cycle 3 of chemotherapy (pre-C3), and global assessments of change (MOST-Change) pre-C3. Clinicians rated patients’ cancer-related symptoms, performance status, and adverse events. Convergent and divergent validity (Spearman’s correlations), discriminative validity (effect sizes between groups classified by clinician-rated characteristics), and responsiveness (paired t tests in patients expected to experience clinically meaningful change) were assessed.
Results:
Of 948 recruits, 903 completed PROMs at baseline and 685 pre-C3. Baseline symptom burden was substantial for PRR-ROC and PPS-ROC ≥ 3. MOSTv2 has 24 items and five multi-item scales: abdominal symptoms (MOST-Abdo), disease or treatment-related symptoms (MOST-DorT), chemotherapy-related symptoms (MOST-Chemo), psychological symptoms (MOST-Psych), and MOST-Well-being. Correlations confirmed concurrent and divergent validity. Discriminative validity was confirmed by effect sizes that conformed with a priori hypotheses. MOST-Abdo was responsive to improvements in abdominal symptoms and MOST-Chemo detected the adverse effects of chemotherapy.
Conclusions:
The MOSTv2 validly quantifies patient-reported symptom burden, adverse effects, and symptom benefit in ROC, and as such is fit-for-purpose for clinical trials of palliative chemotherapy in ROC. Further research is required to assess test–retest reliability
European Society of Gynecological Oncology Statement on Fibroid and Uterine Morcellation
Recently, there has been an intense discussion about the issue of fibroid and uterine morcellation in relation to the risk of unrecognized uterine sarcoma spread. Morcellation can negatively influence the prognosis of patients, and transecting the specimen into pieces prevents the pathologist from performing proper disease staging. Many societies have published their statements regarding this issue. The European Society for Gynecological Oncology has established a working group of clinicians involved in diagnostics and treatment of oncogynecological patients to provide a statement from the oncological point of view. Leiomyosarcomas and undifferentiated endometrial sarcomas have generally dismal prognosis, whereas low-grade endometrial stromal sarcomas and adenosarcomas have variable prognosis based on their stage. A focus on the detection of patients at risk of having a sarcoma should be mandatory before every surgery where morcellation is planned by evaluation of risk factors (African American descent, previous pelvic irradiation, use of tamoxifen, rapid lesion growth particularly in postmenopausal patients) and exclusion of patients with any suspicious ultrasonographic signs. Preoperative endometrial biopsy should be mandatory, although the sensitivity to detect sarcomas is low. An indication for myomectomy should be used only in patients with pregnancy plans; otherwise en bloc hysterectomy is preferred in both symptomatic and postmenopausal patients. Eliminating the technique of morcellation could lead to an increased morbidity in low-risk patients; therefore, after thorough preoperative evaluation and discussion with patients, morcellation still has its place in the armamentarium of gynecologic surgery
Design and Organization of the Dexamethasone, Light Anesthesia and Tight Glucose Control (DeLiT) Trial: a factorial trial evaluating the effects of corticosteroids, glucose control, and depth-of-anesthesia on perioperative inflammation and morbidity from major non-cardiac surgery
<p>Abstract</p> <p>Background</p> <p>The perioperative period is characterized by an intense inflammatory response. Perioperative inflammation promotes postoperative morbidity and increases mortality. Blunting the inflammatory response to surgical trauma might thus improve perioperative outcomes. We are studying three interventions that potentially modulate perioperative inflammation: corticosteroids, tight glucose control, and light anesthesia.</p> <p>Methods/Design</p> <p>The DeLiT Trial is a factorial randomized single-center trial of dexamethasone vs placebo, intraoperative tight vs. conventional glucose control, and light vs deep anesthesia in patients undergoing major non-cardiac surgery. Anesthetic depth will be estimated with Bispectral Index (BIS) monitoring (Aspect medical, Newton, MA). The primary outcome is a composite of major postoperative morbidity including myocardial infarction, stroke, sepsis, and 30-day mortality. C-reactive protein, a measure of the inflammatory response, will be evaluated as a secondary outcome. One-year all-cause mortality as well as post-operative delirium will be additional secondary outcomes. We will enroll up to 970 patients which will provide 90% power to detect a 40% reduction in the primary outcome, including interim analyses for efficacy and futility at 25%, 50% and 75% enrollment.</p> <p>Discussion</p> <p>The DeLiT trial started in February 2007. We expect to reach our second interim analysis point in 2010. This large randomized controlled trial will provide a reliable assessment of the effects of corticosteroids, glucose control, and depth-of-anesthesia on perioperative inflammation and morbidity from major non-cardiac surgery. The factorial design will enable us to simultaneously study the effects of the three interventions in the same population, both individually and in different combinations. Such a design is an economically efficient way to study the three interventions in one clinical trial vs three.</p> <p>Trial registration</p> <p><b>This trial is registered at </b>Clinicaltrials.gov <b>#</b>: NTC00433251</p
Aberrant Cell Cycle Regulation in Cervical Carcinoma
Carcinoma of the uterine cervix is one of the most common malignancies among women worldwide. Human papillomaviruses (HPV) have been identified as the major etiological factor in cervical carcinogenesis. However, the time lag between HPV infection and the diagnosis of cancer indicates that multiple steps, as well as multiple factors, may be necessary for the development of cervical cancer. The development and progression of cervical carcinoma have been shown to be dependent on various genetic and epigenetic events, especially alterations in the cell cycle checkpoint machinery. In mammalian cells, control of the cell cycle is regulated by the activity of cyclin-dependent kinases (CDKs) and their essential activating coenzymes, the cyclins. Generally, CDKs, cyclins, and CDK inhibitors function within several pathways, including the p16INK4A-cyclin D1-CDK4/6-pRb-E2F, p21WAF1-p27KIP1-cyclinE-CDK2, and p14ARF-MDM2-p53 pathways. The results from several studies showed aberrant regulation of several cell cycle proteins, such as cyclin D, cyclin E, p16INK4A, p21WAF1, and p27KIP1, as characteristic features of HPV-infected and HPV E6/E7 oncogene-expressing cervical carcinomas and their precursors. These data suggested further that interactions of viral proteins with host cellular proteins, particularly cell cycle proteins, are involved in the activation or repression of cell cycle progression in cervical carcinogenesis
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