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1.
Mod Pathol ; 32(8): 1197-1209, 2019 07.
Article in English | MEDLINE | ID: mdl-30962504

ABSTRACT

DNA was obtained from matching micro-dissected, primary tumor cells, paired metastases, and peripheral blood mononuclear cells (germline) from patients with appendiceal mucinous neoplasms. We compared specimens from patient cohorts comprising low-grade adenomucinous neoplasm versus high-grade mucinous adenocarcinoma using a targeted, amplicon sequencing panel of 409 cancer related genes (Ion Torrent Comprehensive Cancer Panel, Thermo-Fisher, Waltham, MA). Copy number variants, single nucleotide variants and small insertions/deletions were identified using a multiplex algorithm pipeline (GATK, VarScan2, MuTect2, SIFT, SIFT-INDEL, PolyPhen-2, Provean). There were significantly more damaging variants in high-grade versus low-grade tumor cohorts. Both cohorts contained damaging, heterozygous germline variants (catenin ß1; notch receptor 1 and 4) in pathways associated with cell-lineage specification (WNT, NOTCH). Damaging, somatic KRAS proto-oncogene, GTPase mutations were present in both cohorts, while somatic GNAS complex locus mutations were confined to low-grade neoplasms. Variants predominantly affected transcription factors, kinases, and stem cell signaling molecules in canonical pathways including epithelial to mesenchymal transition, stem cell pluripotency, p53, PTEN, and NF-қB signaling pathways. High-grade tumors demonstrated MYC proto-oncogene, bHLH transcription factor (MYC) and death domain associated protein (DAXX) amplification and damaging somatic variants in tumor protein p53 (TP53), likely to amplify an aggressive phenotype. Damaging APC, WNT signaling pathway regulator (APC) deletions were identified in metastatic tissue of both cohorts suggesting a role in invasive disease. Our data suggest that germline dysregulation of WNT and/or NOTCH pathways predisposes patients toward a secretory cell phenotype (i.e., goblet-like cells) upon acquisition of somatic KRAS mutations. Additional somatically acquired variants activating oncogenes MYC and DAXX and inhibiting the critical tumor suppressor, tumor protein TP53, were consistent with manifestation of a high-grade phenotype. These additional changes within the epithelial to mesenchymal transition signaling network (WNT, NOTCH, RAS/ERK/PI3K, PTEN, NF-қB), produce aggressive high-grade tumor characteristics by actively driving cells towards dedifferentiation, proliferation, and migration.


Subject(s)
Adenocarcinoma, Mucinous/genetics , Appendiceal Neoplasms/genetics , Biomarkers, Tumor/genetics , DNA Mutational Analysis , Gene Dosage , High-Throughput Nucleotide Sequencing , Mutation , Polymorphism, Single Nucleotide , Adenocarcinoma, Mucinous/mortality , Adenocarcinoma, Mucinous/pathology , Adenocarcinoma, Mucinous/surgery , Appendiceal Neoplasms/mortality , Appendiceal Neoplasms/pathology , Appendiceal Neoplasms/surgery , DNA Copy Number Variations , Diagnosis, Differential , Gene Amplification , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , Genetic Predisposition to Disease , Humans , Neoplasm Grading , Phenotype , Predictive Value of Tests , Proto-Oncogene Mas
2.
J Antimicrob Chemother ; 72(11): 3181-3186, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-28961759

ABSTRACT

OBJECTIVES: To examine antimicrobial susceptibility patterns and predictors of resistance among Shigella isolates in New South Wales (NSW), Australia during 2013-14 with emphasis on azithromycin. METHODS: Cross-sectional analysis of all shigellosis cases (160) notified to public health authorities in NSW, Australia was performed. RESULTS: Among 160 Shigella isolates tested, 139 (86.9%) were susceptible to azithromycin, 104 (65.0%) to ciprofloxacin and 38 (23.7%) to co-trimoxazole. Ciprofloxacin resistance was 1.9 times more common in infections acquired in Australia compared with those acquired overseas, while azithromycin resistance was 8.5 times more common in males. CONCLUSIONS: We recommend ongoing reconsideration of guidelines for the treatment of shigellosis based on emerging resistance patterns. First-line therapy may need to be reconsidered based on local resistance rates due to common resistance to co-trimoxazole and ciprofloxacin. We recommend culture and susceptibility testing for suspected and proven shigellosis. Azithromycin susceptibility breakpoints for Shigella species may need to be species specific.


Subject(s)
Anti-Bacterial Agents/pharmacology , Azithromycin/pharmacology , Drug Resistance, Multiple, Bacterial , Dysentery, Bacillary/epidemiology , Dysentery, Bacillary/microbiology , Shigella/drug effects , Adolescent , Adult , Aged , Anti-Bacterial Agents/therapeutic use , Australia/epidemiology , Azithromycin/therapeutic use , Child , Child, Preschool , Ciprofloxacin/pharmacology , Ciprofloxacin/therapeutic use , Cross-Sectional Studies , Dysentery, Bacillary/drug therapy , Female , Humans , Logistic Models , Male , Microbial Sensitivity Tests , Middle Aged , New South Wales/epidemiology , Practice Guidelines as Topic , Young Adult
3.
Aust Health Rev ; 36(3): 284-9, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22935119

ABSTRACT

OBJECTIVE: The objective of this paper is to present and provide justification for a framework to improve evidence-informed management decision-making among health service managers. Three research questions informed the study: How have different perspectives influenced how evidence has been defined? What are the barriers to the practice of evidence-informed decision-making (EIDM)? What are the factors that may encourage the application of evidence to guide management decision-making processes? METHODS: A literature review was conducted to identify studies that examined the practice of EIDM among health service managers. Information relevant to the three research questions was collectively analysed, compared and contrasted based on their relevance to the EIDM process. CONCLUSION: Several factors have played different but significant roles in affecting the practice of EIDM among health service managers. Although interaction between these factors is complex, the framework developed in this paper may guide the development of strategies to encourage and improve the utilisation of evidence in management decision-making process.


Subject(s)
Decision Making, Organizational , Evidence-Based Medicine , Health Facility Administrators , Quality Improvement/organization & administration , Australia , Humans , National Health Programs , Risk Management
4.
Ophthalmology ; 114(10): 1925-31, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17719643

ABSTRACT

PURPOSE: Chromosome 3 loss and chromosome 8 gains in uveal melanoma are associated with metastatic death. Since 1999, we have offered cytogenetic analysis to patients treated by local resection or enucleation. This study correlated our cytogenetic results with clinical and histologic predictors and disease-specific mortality. DESIGN: Nonrandomized case series. PARTICIPANTS: Three hundred fifty-six patients with uveal melanoma with data on chromosome 3 and chromosome 8. METHODS: Tumor diameter was measured by echography. Cell type, presence of closed connective tissue loops, and mitotic rate were determined histopathologically. Fluorescence in-situ hybridization was performed using centromeric probes for chromosomes 3 and 8 and for c-myc. Patients were flagged at the National Health Service Cancer Registry, which notified us of any deaths. Statistics included Cox multivariate analysis and Kaplan-Meier analysis. MAIN OUTCOME MEASURES: Disease-specific mortality, according to clinical, histologic and cytogenetic features as well as correlation between cytogenetic variables and other mortality predictors, including a predictive index. RESULTS: The patients had a mean age of 61.9 years. The tumors showed no cytogenetic abnormalities of chromosomes 3 or 8 in 42%, chromosome 8 gains in 11%, monosomy 3 in 21%, and both abnormalities in 27%. These correlated with ciliary body involvement (P<0.001), extraocular spread (P = 0.007), large basal tumor diameter (P<0.001), epithelioid cellularity (P<0.001), closed connective tissue loops (P<0.001), and mitotic rate exceeding 4/40 high power fields (P<0.001). By the study close, 76 patients had died (67 from metastasis). Cox multivariate analysis showed the most significant factors to be basal tumor diameter (P<0.001), monosomy 3 (P<0.001), and epithelioid cellularity (P = 0.004). A predictive index (PI) was derived from these variables. Kaplan-Meier analysis showed that 5-year metastatic death rates ranged from 0% in 84 patients with low-grade melanoma (PI<19) to 66% in 100 patients with high-grade tumor (PI>26; 95% confidence interval, 53%-80%). CONCLUSION: Cytogenetic analysis of chromosomes 3 and 8 enhances prediction of disease-specific mortality after treatment of uveal melanoma but must be interpreted together with tumor diameter and cell type.


Subject(s)
Chromosome Aberrations , Chromosomes, Human, Pair 3/genetics , Chromosomes, Human, Pair 8/genetics , Melanoma/genetics , Uveal Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Biopsy, Needle , Brachytherapy , Cytogenetic Analysis , Eye Enucleation , Female , Humans , Hyperthermia, Induced , In Situ Hybridization, Fluorescence , Male , Melanoma/mortality , Melanoma/pathology , Melanoma/therapy , Middle Aged , Mitotic Index , Radiotherapy, High-Energy , Uveal Neoplasms/mortality , Uveal Neoplasms/pathology , Uveal Neoplasms/therapy
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