90 research outputs found

    Tegumentary leishmaniasis and coinfections other than HIV

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    <div><p>Background</p><p>Tegumentary leishmaniasis (TL) is a disease of skin and/or mucosal tissues caused by <i>Leishmania</i> parasites. TL patients may concurrently carry other pathogens, which may influence the clinical outcome of TL.</p><p>Methodology and principal findings</p><p>This review focuses on the frequency of TL coinfections in human populations, interactions between <i>Leishmania</i> and other pathogens in animal models and human subjects, and implications of TL coinfections for clinical practice. For the purpose of this review, TL is defined as all forms of cutaneous (localised, disseminated, or diffuse) and mucocutaneous leishmaniasis. Human immunodeficiency virus (HIV) coinfection, superinfection with skin bacteria, and skin manifestations of visceral leishmaniasis are not included. We searched MEDLINE and other databases and included 73 records: 21 experimental studies in animals and 52 studies about human subjects (mainly cross-sectional and case studies). Several reports describe the frequency of <i>Trypanosoma cruzi</i> coinfection in TL patients in Argentina (about 41%) and the frequency of helminthiasis in TL patients in Brazil (15% to 88%). Different hypotheses have been explored about mechanisms of interaction between different microorganisms, but no clear answers emerge. Such interactions may involve innate immunity coupled with regulatory networks that affect quality and quantity of acquired immune responses. Diagnostic problems may occur when concurrent infections cause similar lesions (e.g., TL and leprosy), when different pathogens are present in the same lesions (e.g., <i>Leishmania</i> and <i>Sporothrix schenckii</i>), or when similarities between phylogenetically close pathogens affect accuracy of diagnostic tests (e.g., serology for leishmaniasis and Chagas disease). Some coinfections (e.g., helminthiasis) appear to reduce the effectiveness of antileishmanial treatment, and drug combinations may cause cumulative adverse effects.</p><p>Conclusions and significance</p><p>In patients with TL, coinfection is frequent, it can lead to diagnostic errors and delays, and it can influence the effectiveness and safety of treatment. More research is needed to unravel how coinfections interfere with the pathogenesis of TL.</p></div

    Dynamics of cancer cell subpopulations in primary and metastatic colorectal tumors

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    Intratumor heterogeneity—heterogeneity of cancer cells within a single tumor—is considered one of the most problematic factors of treatment. Genetic heterogeneity, such as in somatic mutations and chromosome aberrations, is a common characteristic of human solid tumors and is probably the basis of biological heterogeneity. Using mutations in APC, TP53 and KRAS as markers to identify distinct colorectal cancer subpopulations, we analyzed a total of 42 primary colorectal cancer tissues and six paired liver metastases with multipoint microsampling, which enabled analysis of mutation patterns and allelic imbalances with a resolution of 0.01 mm2 (about 200 cells). There was usually more than one subpopulation in each primary tumor. Only two of 15 (13.3%) cases with three gene mutations and eight of 27 (29.6%) cases with two gene mutations had a single subpopulation. Cells with mutations in all of the examined genes usually constituted the major population. Multipoint microsampling of six primary and metastatic tumor pairs revealed that the majority of discrepancies in mutation patterns found with the bulk tissue analysis were due to loss of subpopulations in the metastatic tissues. In addition, multipoint microsampling uncovered substantial changes in subpopulations that were not detected with bulk tissue analysis. Specifically, the proportion of KRAS mutation-negative subpopulations increased in the metastatic tumors of four cases. Because KRAS mutation status is linked to cetuximab/panitumumab efficacy, subpopulation dynamics could lead to differences in response to cetuximab/panitumumab in primary versus metastatic tumors

    Most Patients with Colorectal Tumors at Young Age Do Not Visit a Cancer Genetics Clinic

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    Contains fulltext : 70595.pdf (publisher's version ) (Open Access)PURPOSE: This study examined the referral process for genetic counseling at a cancer genetics clinic in patients with colorectal cancer and to search for determinants of variation in this referral process. METHODS: Patients who were recently diagnosed with colorectal cancer at a young age or multiple cancers associated with Lynch syndrome, hereditary nonpolyposis colorectal cancer, (N = 119) were selected from PALGA, the nationwide network and registry of histopathology and cytopathology in the Netherlands. In a retrospective analysis, we examined whether these patients visited a cancer genetics clinic and identified determinants for referral to such a clinic. Factors of patients, professional practice, and hospital setting were explored with logistic regression modeling. RESULTS: Thirty-six (30 percent) patients visited a cancer genetics clinic. Seventy percent of patients whom the surgeon referred to a cancer genetics clinic decided to visit such a clinic. Analysis of determinants showed that patients with whom the surgeon discussed referral and that were treated in a teaching hospital were more likely to visit a cancer genetics clinic. CONCLUSION: The referral process is not optimally carried out. To deliver optimal care for patients suspected of hereditary colorectal cancer, this process must be improved with interventions focusing on patient referral by surgeons and raising awareness in nonteaching hospitals

    Electronic reminders for pathologists promote recognition of patients at risk for Lynch syndrome: cluster-randomised controlled trial

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    We investigated success factors for the introduction of a guideline on recognition of Lynch syndrome in patients recently diagnosed with colorectal cancer (CRC) below age 50 or a second CRC below age 70. Pathologists were asked to start microsatellite instability (MSI) testing and report to surgeons with the advice to consider genetic counselling when MSI test or family history was positive. A multicentre cluster-randomised controlled trial (ClinicalTrials.gov, number NCT00141466) was performed in 12 pathology laboratories (clusters), serving 29 community hospitals. All received an introduction to the new guideline. In the intervention group, surgeons received education and tumour test result reminders; pathologists were provided with inclusion criteria cards, an electronic patient inclusion reminder system and feedback on inclusion. Two hundred sixty-six CRC patients were eligible for recognition as at risk for Lynch syndrome. The actual recognition was 18% more successful in the intervention as compared to the control arm (77% (120 of 156) compared to 59% (65 of 110)), with an adjusted odds ratio (OR) = 2.8 (95% confidence interval (CI) 1.1–7.0). The electronic reminder system for pathologists was most strongly associated with recognition of high-risk patients, OR = 4.2 (95% CI 1.7–10.1). An electronic reminder system for pathologists appeared effective for adherence to a new complex guideline and will enhance the recognition of Lynch syndrome

    Psychological distress in newly diagnosed colorectal cancer patients following microsatellite instability testing for Lynch syndrome on the pathologist’s initiative

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    According to the Dutch Guideline on Hereditary Colorectal Cancer published in 2008, patients with recently diagnosed colorectal cancer (CRC) should undergo microsatellite instability (MSI) testing by a pathologist immediately after tumour resection if they are younger than 50 years, or if a second CRC has been diagnosed before the age of 70 years, owing to the high risk of Lynch syndrome (MIPA). The aim of the present MIPAPS study was to investigate general distress and cancer-specific distress following MSI testing. From March 2007 to September 2009, 400 patients who had been tested for MSI after newly diagnosed CRC were recruited from 30 Dutch hospitals. Levels of general distress (SCL-90) and cancer-specific distress (IES) were assessed immediately after MSI result disclosure (T1) and 6 months later (T2). Response rates were 23/77 (30%) in the MSI-positive patients and 58/323 (18%) in the MSI-negative patients. Levels of general distress and cancer-specific distress were moderate. In the MSI-positive group, 27% of the patients had high general distress at T1 versus 18% at T2 (p = 0.5), whereas in the MSI-negative group, these percentage were 14 and 18% (p = 0.6), respectively. At T1 and T2, cancer-specific distress rates in the MSI-positive group and MSI-negative group were 39 versus 27% (p = 0.3) and 38 versus 36% (p = 1.0), respectively. High levels of general distress were correlated with female gender, low social support and high perceived cancer risk. Moderate levels of distress were observed after MSI testing, similar to those found in other patients diagnosed with CRC. Immediately after result disclosure, high cancer-specific distress was observed in 40% of the MSI-positive patients

    Immune Cell Recruitment and Cell-Based System for Cancer Therapy

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    Immune cells, such as cytotoxic T lymphocytes, natural killer cells, B cells, and dendritic cells, have a central role in cancer immunotherapy. Conventional studies of cancer immunotherapy have focused mainly on the search for an efficient means to prime/activate tumor-associated antigen-specific immunity. A systematic understanding of the molecular basis of the trafficking and biodistribution of immune cells, however, is important for the development of more efficacious cancer immunotherapies. It is well established that the basis and premise of immunotherapy is the accumulation of effective immune cells in tumor tissues. Therefore, it is crucial to control the distribution of immune cells to optimize cancer immunotherapy. Recent characterization of various chemokines and chemokine receptors in the immune system has increased our knowledge of the regulatory mechanisms of the immune response and tolerance based on immune cell localization. Here, we review the immune cell recruitment and cell-based systems that can potentially control the systemic pharmacokinetics of immune cells and, in particular, focus on cell migrating molecules, i.e., chemokines, and their receptors, and their use in cancer immunotherapy

    Multi-scale genomic, transcriptomic and proteomic analysis of colorectal cancer cell lines to identify novel biomarkers

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    This work was partially funded by the Strategic Educational Pathways Scholarship (Malta). The scholarship is part-financed by the European Union – European Social Fund (ESF) under Operational Programme II – Cohesion Policy 2007-2013, “Empowering People for More Jobs and a Better Quality of Life”. This project was additionally funded by Medical Research Scotland.Selecting colorectal cancer (CRC) patients likely to respond to therapy remains a clinical challenge. The objectives of this study were to establish which genes were differentially expressed with respect to treatment sensitivity and relate this to copy number in a panel of 15 CRC cell lines. Copy number variations of the identified genes were assessed in a cohort of CRCs. IC50’s were measured for 5-fluorouracil, oxaliplatin, and BEZ-235, a PI3K/mTOR inhibitor. Cell lines were profiled using array comparative genomic hybridisation, Illumina gene expression analysis, reverse phase protein arrays, and targeted sequencing of KRAS hotspot mutations. Frequent gains were observed at 2p, 3q, 5p, 7p, 7q, 8q, 12p, 13q, 14q, and 17q and losses at 2q, 3p, 5q, 8p, 9p, 9q, 14q, 18q, and 20p. Frequently gained regions contained EGFR, PIK3CA, MYC, SMO, TRIB1, FZD1, and BRCA2, while frequently lost regions contained FHIT and MACROD2. TRIB1 was selected for further study. Gene enrichment analysis showed that differentially expressed genes with respect to treatment response were involved in Wnt signalling, EGF receptor signalling, apoptosis, cell cycle, and angiogenesis. Stepwise integration of copy number and gene expression data yielded 47 candidate genes that were significantly correlated. PDCD6 was differentially expressed in all three treatment responses. Tissue microarrays were constructed for a cohort of 118 CRC patients and TRIB1 and MYC amplifications were measured using fluorescence in situ hybridisation. TRIB1 and MYC were amplified in 14.5% and 7.4% of the cohort, respectively, and these amplifications were significantly correlated (p≤0.0001). TRIB1 protein expression in the patient cohort was significantly correlated with pERK, Akt, and Caspase 3 expression. In conclusion, a set of candidate predictive biomarkers for 5-fluorouracil, oxaliplatin, and BEZ235 are described that warrant further study. Amplification of the putative oncogene TRIB1 has been described for the first time in a cohort of CRC patients.Publisher PDFPeer reviewe

    Prediction of disability-free survival in healthy older people

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    Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disability-free survival outcome was defined as absence of dementia, persistent disability or death. Selection of potential predictors from amongst 25 biomedical, psychosocial and lifestyle variables including recognized geriatric risk factors, utilizing a machine-learning approach. Separate models were developed for men and women. The selected predictors were evaluated in a multivariable Cox proportional hazards model and validated internally by bootstrapping. We included 19,114 Australian and US participants aged ≥65 years (median 74 years, IQR 71.6–77.7). Common predictors of a worse prognosis in both sexes included higher age, lower Modified Mini-Mental State Examination score, lower gait speed, lower grip strength and abnormal (low or elevated) body mass index. Additional risk factors for men included current smoking, and abnormal eGFR. In women, diabetes and depression were additional predictors. The biased-corrected areas under the receiver operating characteristic curves for the final prognostic models at 5 years were 0.72 for men and 0.75 for women. Final models showed good calibration between the observed and predicted risks. We developed a prediction model in which age, cognitive function and gait speed were the strongest predictors of disability-free survival in healthy older people. Trial registration Clinicaltrials.gov (NCT01038583

    Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

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    Background: Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 antibodies. We aimed to evaluate the safety and efficacy of convalescent plasma therapy in patients admitted to hospital with COVID-19. Methods: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. The trial is underway at 177 NHS hospitals from across the UK. Eligible and consenting patients were randomly assigned (1:1) to receive either usual care alone (usual care group) or usual care plus high-titre convalescent plasma (convalescent plasma group). The primary outcome was 28-day mortality, analysed on an intention-to-treat basis. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings: Between May 28, 2020, and Jan 15, 2021, 11558 (71%) of 16287 patients enrolled in RECOVERY were eligible to receive convalescent plasma and were assigned to either the convalescent plasma group or the usual care group. There was no significant difference in 28-day mortality between the two groups: 1399 (24%) of 5795 patients in the convalescent plasma group and 1408 (24%) of 5763 patients in the usual care group died within 28 days (rate ratio 1·00, 95% CI 0·93–1·07; p=0·95). The 28-day mortality rate ratio was similar in all prespecified subgroups of patients, including in those patients without detectable SARS-CoV-2 antibodies at randomisation. Allocation to convalescent plasma had no significant effect on the proportion of patients discharged from hospital within 28 days (3832 [66%] patients in the convalescent plasma group vs 3822 [66%] patients in the usual care group; rate ratio 0·99, 95% CI 0·94–1·03; p=0·57). Among those not on invasive mechanical ventilation at randomisation, there was no significant difference in the proportion of patients meeting the composite endpoint of progression to invasive mechanical ventilation or death (1568 [29%] of 5493 patients in the convalescent plasma group vs 1568 [29%] of 5448 patients in the usual care group; rate ratio 0·99, 95% CI 0·93–1·05; p=0·79). Interpretation: In patients hospitalised with COVID-19, high-titre convalescent plasma did not improve survival or other prespecified clinical outcomes. Funding: UK Research and Innovation (Medical Research Council) and National Institute of Health Research
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