134 research outputs found
Tp53 mutation is a prognostic factor in lower grade glioma and may influence chemotherapy efficacy
Background: Identification of prognostic biomarkers in cancers is a crucial step to improve overall survival (OS). Although mutations in tumour protein 53 (TP53) is prevalent in astrocytoma, the prognostic effects of TP53 mutation are unclear. Methods: In this retrospective study, we sequenced TP53 exons 1 to 10 in a cohort of 102 lower-grade glioma (LGG) subtypes and determined the prognostic effects of TP53 mutation in astrocytoma and oligodendroglioma. Publicly available datasets were analysed to confirm the findings. Results: In astrocytoma, mutations in TP53 codon 273 were associated with a significantly increased OS compared to the TP53 wild-type (HR (95% CI): 0.169 (0.036–0.766), p = 0.021). Public datasets confirmed these findings. TP53 codon 273 mutant astrocytomas were significantly more chemosensitive than TP53 wild-type astrocytomas (HR (95% CI): 0.344 (0.13–0.88), p = 0.0148). Post-chemotherapy, a significant correlation between TP53 and YAP1 mRNA was found (p = 0.01). In O (6)-methylguanine methyltransferase (MGMT) unmethylated chemotherapy-treated astrocytoma, both TP53 codon 273 and YAP1 mRNA were significant prognostic markers. In oligodendroglioma, TP53 mutations were associated with significantly decreased OS. Conclusions: Based on these findings, we propose that certain TP53 mutant astrocytomas are chemosensitive through the involvement of YAP1, and we outline a potential mech-anism. Thus, TP53 mutations may be key drivers of astrocytoma therapeutic efficacy and influence survival outcomes
Challenges in perioperative fluid management and anticoagulant therapy in a woman with cardio-pulmonary-renal disease diagnosed with preinvasive breast carcinoma
An elderly woman with preinvasive breast cancer, atrial fibrillation, coronary artery-pulmonary artery fistula, pulmonary hypertension and Stage 4 diabetic nephropathy underwent a mastectomy and sentinel lymph node biopsy. Managing her perioperative fluid balance and anticoagulation treatment were challenging. Having a malignancy, atrial fibrillation plus underhydration will increase her risk of hypercoagulation. However, fluid overload will lead to pulmonary oedema which will decrease her oxygenation further in pulmonary hypertension. Cessation of anticoagulation also increased the risk of hypercoagulation. Anticoagulant therapy increases the risk of a perioperative wound haematoma, which may require another general anaesthesia for identification and arrest of the bleeding source and haematoma evacuation. A haematoma will also increase the risk of surgical site infection; especially as a diabetic. Her anticoagulant therapy (rivoroxaban) was stopped four days preoperatively. Her ejection fraction was 50%, with Grade II diastolic dysfunction and TAPSE 0.6 cm. Her CHA2DS2-VASc Score was 5. Perioperatively, intraarterial cannulation was connected to the FloTracâ„¢ sensor and EV1000â„¢ monitor. Her fluid management was monitored using goal directed (GD) fluid therapy. The patient underwent surgery successfully and her anticoagulant therapy was recommenced 14 days postoperatively
Endovascular covered stenting for the management of post-percutaneous nephrolithotomy renal pseudoaneurysm: a case report
<p>Abstract</p> <p>Introduction</p> <p>Intrarenal pseudoaneurysm is a rare, yet clinically significant, complication of percutaneous nephrolithotomy. A high index of clinical suspicion is necessary in order to recognize pseudoaneurysm as the cause of delayed bleeding after percutaneous nephrolithotomy and angiography confirms the diagnosis which allows endovascular management.</p> <p>Case presentation</p> <p>We present a case of a 65-year old Caucasian woman who underwent percutaneous nephrolithotomy in the supine position for a two centimetre renal calculus. The postoperative course was complicated by persistent bleeding due to a renal pseudoaneurysm. The vascular lesion was successfully managed by endovascular exclusion through the use of a covered stent graft. We report the first successful use of this method for the management of iatrogenic pseudoaneurysm in a branch of the left renal artery and we focus on the imaging findings, technical details, advantages and limitations of this technique.</p> <p>Conclusion</p> <p>As a result of its high efficacy, interventional radiology has largely replaced open surgery for the management of renal pseudoaneurysm related to percutaneous nephrolithotomy. Recent technical advancements have allowed the use of covered stent grafts as an alternative to embolisation for the angiographic management of visceral artery pseudoaneurysm located in other organs. This novel technique allows the endovascular exclusion of the pseudoaneurysm, without compromising arterial supply to the end-structures - an advantage of critical importance in organs supplied by segmental arteries - in the absence of collateral vasculature, such as the kidney.</p
Large introns in relation to alternative splicing and gene evolution: a case study of Drosophila bruno-3
Background:
Alternative splicing (AS) of maturing mRNA can generate structurally and functionally distinct transcripts from the same gene. Recent bioinformatic analyses of available genome databases inferred a positive correlation between intron length and AS. To study the interplay between intron length and AS empirically and in more detail, we analyzed the diversity of alternatively spliced transcripts (ASTs) in the Drosophila RNA-binding Bruno-3 (Bru-3) gene. This gene was known to encode thirteen exons separated by introns of diverse sizes, ranging from 71 to 41,973 nucleotides in D. melanogaster. Although Bru-3's structure is expected to be conducive to AS, only two ASTs of this gene were previously described.
Results:
Cloning of RT-PCR products of the entire ORF from four species representing three diverged Drosophila lineages provided an evolutionary perspective, high sensitivity, and long-range contiguity of splice choices currently unattainable by high-throughput methods. Consequently, we identified three new exons, a new exon fragment and thirty-three previously unknown ASTs of Bru-3. All exon-skipping events in the gene were mapped to the exons surrounded by introns of at least 800 nucleotides, whereas exons split by introns of less than 250 nucleotides were always spliced contiguously in mRNA. Cases of exon loss and creation during Bru-3 evolution in Drosophila were also localized within large introns. Notably, we identified a true de novo exon gain: exon 8 was created along the lineage of the obscura group from intronic sequence between cryptic splice sites conserved among all Drosophila species surveyed. Exon 8 was included in mature mRNA by the species representing all the major branches of the obscura group. To our knowledge, the origin of exon 8 is the first documented case of exonization of intronic sequence outside vertebrates.
Conclusion:
We found that large introns can promote AS via exon-skipping and exon turnover during evolution likely due to frequent errors in their removal from maturing mRNA. Large introns could be a reservoir of genetic diversity, because they have a greater number of mutable sites than short introns. Taken together, gene structure can constrain and/or promote gene evolution
Educating Cancer Prevention Researchers in Emerging Biobehavioral Models: Lessons Learned
To increase the adoption of transdisciplinary research methods among future cancer prevention investigators, faculty members from The University of Texas MD Anderson Cancer Center developed a graduate-level course in biobehavioral methods in cancer prevention research. Two instructors paired by topic and area of expertise offered an hour-long lecture-based seminar every week for 15Â weeks during the spring semester of 2010. Students and presenters both evaluated the overall course content and delivery method, as well as each session. A total of 11 students and 22 presenters participated in the course. In each class session, one presenter was from a behavioral science background,and the other was from a biological sciences background. Both presenters and students expressed overall satisfaction with the content and format of the course. The presentation of topics from a transdisciplinary perspective and interaction with presenters from both biological and behavioral sciences are valuable and can help junior researchers prepare to meet the emerging challenges in cancer prevention research
Progress towards implementation of ACT malaria case-management in public health facilities in the Republic of Sudan: a cluster-sample survey
<p>Abstract</p> <p>Background</p> <p>Effective malaria case-management based on artemisinin-based combination therapy (ACT) and parasitological diagnosis is a major pillar within the 2007-2012 National Malaria Strategic Plan in the Sudan. Three years after the launch of the strategy a health facility survey was undertaken to evaluate case-management practices and readiness of the health facilities and health workers to implement a new malaria case-management strategy.</p> <p>Methods</p> <p>A cross-sectional, cluster sample survey was undertaken at public health facilities in 15 states of Sudan. Data were collected using quality-of-care assessment methods. The main outcomes were the proportions of facilities with ACTs and malaria diagnostics; proportions of health workers exposed to malaria related health systems support activities; and composite and individual indicators of case-management practices for febrile outpatients stratified by age, availability of ACTs and diagnostics, use of malaria diagnostics, and test result.</p> <p>Results</p> <p>We evaluated 244 facilities, 294 health workers and 1,643 consultations for febrile outpatients (425 < 5 years and 1,218 ≥ 5 years). Health facility and health worker readiness was variable: chloroquine was available at only 5% of facilities, 73% stocked recommended artesunate and sulfadoxine/pyrimethamine (AS+SP), 51% had the capacity to perform parasitological diagnosis, 53% of health workers had received in-service training on ACTs, 24% were trained in the use of malaria Rapid Diagnostic Tests, and 19% had received a supervisory visit including malaria case-management. At all health facilities 46% of febrile patients were parasitologically tested and 35% of patients were both, tested and treated according to test result. At facilities where AS+SP and malaria diagnostics were available 66% of febrile patients were tested and 51% were both, tested and treated according to test result. Among test positive patients 64% were treated with AS+SP but 24% were treated with artemether monotherapy. Among test negative patients only 17% of patients were treated for malaria. The majority of ACT dispensing and counseling practices were suboptimal.</p> <p>Conclusions</p> <p>Five years following change of the policy from chloroquine to ACTs and 3 years before the end of the new malaria strategic plan chloroquine was successfully phased out from public facilities in Sudan, however, an important gap remained in the availability of ACTs, diagnostic capacities and coverage with malaria case-management activities. The national scale-up of diagnostics, using the findings of this survey as well as future qualitative research, should present an opportunity not only to expand existing testing capacities but also to implement effective support interventions to bridge the health systems gaps and support corrective case-management measures, including the discontinuation of artemether monotherapy treatment.</p
Diarrhea, Pneumonia, and Infectious Disease Mortality in Children Aged 5 to 14 Years in India
Background: Little is known about the causes of death in children in India after age five years. The objective of this study is to provide the first ever direct national and sub-national estimates of infectious disease mortality in Indian children aged 5 to 14 years. Methods: A verbal autopsy based assessment of 3 855 deaths is children aged 5 to 14 years from a nationally representative survey of deaths occurring in 2001–03 in 1?1 million homes in India. Results: Infectious diseases accounted for 58 % of all deaths among children aged 5 to 14 years. About 18 % of deaths were due to diarrheal diseases, 10 % due to pneumonia, 8 % due to central nervous system infections, 4 % due to measles, and 12 % due to other infectious diseases. Nationally, in 2005 about 59 000 and 34 000 children aged 5 to 14 years died from diarrheal diseases and pneumonia, corresponding to mortality of 24?1 and 13?9 per 100 000 respectively. Mortality was nearly 50 % higher in girls than in boys for both diarrheal diseases and pneumonia. Conclusions: Approximately 60 % of all deaths in this age group are due to infectious diseases and nearly half of these deaths are due to diarrheal diseases and pneumonia. Mortality in this age group from infectious diseases, and diarrhea i
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