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Find video protocols related to scientific articles indexed in Pubmed.
Timing of antiretroviral therapy after diagnosis of cryptococcal meningitis.
N. Engl. J. Med.
PUBLISHED: 06-26-2014
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Cryptococcal meningitis accounts for 20 to 25% of acquired immunodeficiency syndrome-related deaths in Africa. Antiretroviral therapy (ART) is essential for survival; however, the question of when ART should be initiated after diagnosis of cryptococcal meningitis remains unanswered.
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Analysis of the genome and transcriptome of Cryptococcus neoformans var. grubii reveals complex RNA expression and microevolution leading to virulence attenuation.
PLoS Genet.
PUBLISHED: 04-01-2014
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Cryptococcus neoformans is a pathogenic basidiomycetous yeast responsible for more than 600,000 deaths each year. It occurs as two serotypes (A and D) representing two varieties (i.e. grubii and neoformans, respectively). Here, we sequenced the genome and performed an RNA-Seq-based analysis of the C. neoformans var. grubii transcriptome structure. We determined the chromosomal locations, analyzed the sequence/structural features of the centromeres, and identified origins of replication. The genome was annotated based on automated and manual curation. More than 40,000 introns populating more than 99% of the expressed genes were identified. Although most of these introns are located in the coding DNA sequences (CDS), over 2,000 introns in the untranslated regions (UTRs) were also identified. Poly(A)-containing reads were employed to locate the polyadenylation sites of more than 80% of the genes. Examination of the sequences around these sites revealed a new poly(A)-site-associated motif (AUGHAH). In addition, 1,197 miscRNAs were identified. These miscRNAs can be spliced and/or polyadenylated, but do not appear to have obvious coding capacities. Finally, this genome sequence enabled a comparative analysis of strain H99 variants obtained after laboratory passage. The spectrum of mutations identified provides insights into the genetics underlying the micro-evolution of a laboratory strain, and identifies mutations involved in stress responses, mating efficiency, and virulence.
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AIDS-related mycoses: the way forward.
Trends Microbiol.
PUBLISHED: 03-04-2014
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The contribution of fungal infections to the morbidity and mortality of HIV-infected individuals is largely unrecognized. A recent meeting highlighted several priorities that need to be urgently addressed, including improved epidemiological surveillance, increased availability of existing diagnostics and drugs, more training in the field of medical mycology, and better funding for research and provision of treatment, particularly in developing countries.
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Estrogen receptor, Progesterone receptor, HER2 status and Ki67 index and responsiveness to adjuvant tamoxifen in postmenopausal high-risk breast cancer patients enrolled in the DBCG 77C trial.
Eur. J. Cancer
PUBLISHED: 02-20-2014
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The DBCG 77C trial compared one year of tamoxifen in postmenopausal, steroid-receptor unknown, high-risk breast cancer patients to no adjuvant systemic therapy. After a potential follow-up of 30years we report overall efficacy of the study and results according to subtypes subsequently assessed by immunohistochemistry and fluorescent in situ hybridisation (FISH).
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The Cryptococcus neoformans transcriptome at the site of human meningitis.
MBio
PUBLISHED: 02-06-2014
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Cryptococcus neoformans is the leading cause of fungal meningitis worldwide. Previous studies have characterized the cryptococcal transcriptome under various stress conditions, but a comprehensive profile of the C. neoformans transcriptome in the human host has not been attempted. Here, we extracted RNA from yeast cells taken directly from the cerebrospinal fluid (CSF) of two AIDS patients with cryptococcal meningitis prior to antifungal therapy. The patients were infected with strains of C. neoformans var. grubii of molecular type VNI and VNII. Using RNA-seq, we compared the transcriptional profiles of these strains under three environmental conditions (in vivo CSF, ex vivo CSF, and yeast extract-peptone-dextrose [YPD]). Although we identified a number of differentially expressed genes, single nucleotide variants, and novel genes that were unique to each strain, the overall expression patterns of the two strains were similar under the same environmental conditions. Specifically, yeast cells obtained directly from each patient's CSF were more metabolically active than cells that were incubated ex vivo in CSF. Compared with growth in YPD, some genes were identified as significantly upregulated in both in vivo and ex vivo CSF, and they were associated with genes previously recognized for contributing to pathogenicity. For example, genes with known stress response functions, such as RIM101, ENA1, and CFO1, were regulated similarly in the two clinical strains. Conversely, many genes that were differentially regulated between the two strains appeared to be transporters. These findings establish a platform for further studies of how this yeast survives and produces disease.
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Demand-specific work ability, poor health and working conditions in middle-aged full-time employees.
Appl Ergon
PUBLISHED: 01-29-2014
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We investigated the prevalence of reduced demand-specific work ability, its association with age, gender, education, poor health, and working conditions, and the interaction between poor health and working conditions regarding reduced demand-specific work ability. We used cross-sectional questionnaire data from 3381 full-time employees responding to questions about vocational education, job demands and social support (working conditions), musculoskeletal pain (MSP) and major depression (MD) (poor health) and seven questions about difficulty managing different job demands (reduced demand-specific work ability). Reduced demand-specific work ability varied from 9% to 19% among the 46-year old and from 11% to 21% among the 56-year old. Age was associated with two, gender with four, and education with all measures of reduced demand-specific work ability. MSP was associated with four and MD was associated with six measures of reduced demand-specific work ability. We found no interaction between working conditions and poor health regarding reduced demand-specific work ability.
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Measuring ERCC1 protein expression in cancer specimens: validation of a novel antibody.
Sci Rep
PUBLISHED: 01-03-2014
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Platinum chemotherapy remains part of standard therapies in the management of a variety of cancers. Severe side effects and a high degree of resistance to platinum drugs have led numerous researchers to search for predictive biomarkers, which could aid in identifying patients that are the most likely to respond to therapy. The ERCC1-ERCC4 endonuclease plays a critical role in the repair of platinum-DNA damage and has widely been studied in relation to sensitivity to platinum chemotherapy. The standard method to evaluate ERCC1 protein expression is through the use of immunohistochemistry with monoclonal antibody 8F1, an antibody that was recently found to bind an unrelated protein. The present study determines the specificity of a novel antibody, monoclonal antibody 4F9, and presents a method to evaluate ERCC1 expression in colorectal tumor specimens. Using relevant cell lines as controls, the specificity of antibody 4F9 was tested by immunoblotting, immunohistochemistry and immunofluorescence. Scoring guidelines to aid in the evaluation of ERCC1 tumor expression were developed and evaluated in archival formalin-fixed paraffin embedded colorectal cancer specimens. Antibody 4F9 was found to be specific by all methods applied and it was possible to evaluate the ERCC1 expression in the majority (85%) of colorectal cancer tumor specimens.
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Gene aberrations of RRM1 and RRM2B and outcome of advanced breast cancer after treatment with docetaxel with or without gemcitabine.
BMC Cancer
PUBLISHED: 09-10-2013
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The purpose of the present study was to retrospectively evaluate whether copy number changes of the genes encoding the ribonucleotide reductase subunit M1 (RRM1) and/or subunit M2B (RRM2B) predict sensitivity to gemcitabine administered in combination with docetaxel compared to single agent docetaxel in advanced breast cancer patients.
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How do employees prioritise when they schedule their own shifts?
Ergonomics
PUBLISHED: 07-05-2013
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We investigated how employees prioritised when they scheduled their own shifts and whether priorities depended on age, gender, educational level, cohabitation and health status. We used cross-sectional questionnaire data from the follow-up survey of an intervention study investigating the effect of self-scheduling (n = 317). Intervention group participants were asked about their priorities when scheduling their own shifts succeeded by 17 items covering family/private life, economy, job content, health and sleep. At least half of the participants reported that they were giving high priority to their family life, having consecutive time off, leisure-time activities, rest between shifts, sleep, regularity of their everyday life, health and that the work schedule balanced. Thus, employees consider both their own and the workplaces needs when they have the opportunity to schedule their own shifts. Age, gender, cohabitation and health status were all significantly associated with at least one of these priorities.
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Number of test trials needed for performance stability and interrater reliability of the one leg stand test in patients with a major non-traumatic lower limb amputation.
Gait Posture
PUBLISHED: 07-01-2013
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Balance is beneficial for daily functioning of patients with a lower limb amputation and sometimes assessed by the one-leg stand test (OLST). The aims of the study were to examine (1) the number of trials needed to achieve performance stability, (2) the interrater reliability of the OLST in patients with a major non-traumatic lower limb amputation, and (3) to provide a test procedure.
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An explorative analysis of ERCC1-19q13 copy number aberrations in a chemonaive stage III colorectal cancer cohort.
BMC Cancer
PUBLISHED: 06-10-2013
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Platinum-based chemotherapy has long been used in the treatment of a variety of cancers and functions by inducing DNA damage. ERCC1 and ERCC4 are involved in the removal of this damage and have previously been implicated in resistance to platinum compounds. The aim of the current investigation is to determine the presence, frequency and prognostic impact of ERCC1 or ERCC4 gene copy number alterations in colorectal cancer (CRC).
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Extended cardiac rehabilitation for socially vulnerable patients improves attendance and outcome.
Dan Med J
PUBLISHED: 03-15-2013
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Patients living alone or having a low socioeconomic status are likely to quit cardiac rehabilitation. We aimed to compare patients being offered extended rehabilitation (ERP) with those being offered standard rehabilitation (SRP) as concerns 1) attendance rates and 2) achievement of treatment goals at 12 months.
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Mechanisms of topoisomerase I (TOP1) gene copy number increase in a stage III colorectal cancer patient cohort.
PLoS ONE
PUBLISHED: 02-28-2013
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Topoisomerase I (Top1) is the target of Top1 inhibitor chemotherapy. The TOP1 gene, located at 20q12-q13.1, is frequently detected at elevated copy numbers in colorectal cancer (CRC). The present study explores the mechanism, frequency and prognostic impact of TOP1 gene aberrations in stage III CRC and how these can be detected by fluorescent in situ hybridization (FISH).
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Titan cells in Cryptococcus neoformans: cells with a giant impact.
Curr. Opin. Microbiol.
PUBLISHED: 02-13-2013
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Cryptococcus neoformans is a pathogenic yeast that commonly infects immunocompromised individuals, yet has developed multiple adaptation mechanisms to the host. Several virulence factors (capsule and melanin) have been known for many years. However, this yeast also possesses a morphogenetic program that is still not well characterized. C. neoformans has the ability to dramatically enlarge its size during infection to form titan cells that can reach up to 100?m in cell body diameter, in contrast to typical size cells of 5-7?m. These titan cells pose a problem for the host because they contribute to fungal survival, dissemination to the central nervous system, and possibly even latency. In this review, we will provide an overview of these cells, covering current knowledge about their phenotypic features, mechanism of formation, and their significance during infection.
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Work-life balance among shift workers: results from an intervention study about self-rostering.
Int Arch Occup Environ Health
PUBLISHED: 02-07-2013
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PURPOSE: The aims of the study were to explore the effects of the implementation of IT-based tools for planning of rosters among shift workers on work-family-related outcomes and to interpret the results in light of the different implementation processes. METHODS: A quasi-experimental intervention study was conducted with 12-month follow-up at 14 intervention and 14 reference worksites in Denmark. Workplaces planning to introduce IT-supported self-rostering were recruited, and three different kinds of interventions were implemented. Intervention A and B aimed at increasing workers satisfaction and well-being, while intervention C was designed to optimize the personnel resources. Questionnaire data were collected from 840 employees at baseline and 784 at follow-up. Process evaluation encompassed interviews with about 25 employees and 15 managers at baseline and follow-up. Work-family-related outcomes were work-life conflicts, work-life facilitation, marital conflicts and time with children. RESULTS: An overall decline in work-family conflicts and increase in work-family facilitation were found in the total intervention group. More specifically, in group B, work-family conflicts and marital conflicts decreased while work-family facilitation increased. In group C, work-family conflicts increased while work-family facilitation and time spend with children decreased, and no significant changes were observed in the reference group and in group A. CONCLUSION: An overall positive effect of the implementation of self-rostering was found on the balance between work and private life. However, results from the process evaluation suggested that the organizational aim with the intervention was crucial for the effect.
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Prognostic and predictive value of tumor vascular endothelial growth factor gene amplification in metastatic breast cancer treated with paclitaxel with and without bevacizumab; results from ECOG 2100 trial.
Clin. Cancer Res.
PUBLISHED: 01-22-2013
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Clinically validated biomarkers for anti-angiogenesis agents are not available. We have previously reported associations between candidate VEGFA single-nucleotide polymorphisms (SNP) and overall survival (OS) in E2100. The associations between tumor VEGFA amplification and outcome are evaluated here.
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Predictive biomarkers with potential of converting conventional chemotherapy to targeted therapy in patients with metastatic colorectal cancer.
Scand. J. Gastroenterol.
PUBLISHED: 12-19-2011
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The availability of systemic chemotherapy regimens for the treatment of patients with metastatic colorectal cancer (mCRC) is based on the results from large prospective, randomized studies. The main chemotherapeutic drugs used in treatment of mCRC are the fluoropyrimidines (5-fluorouracil (5-FU); capecitabine) in combination with either oxaliplatin (FOLFOX) or irinotecan (FOLFIRI). The objective response rate to either combination is approximately 50%, where no significant differences with regard to progression free survival or overall survival have been observed. Interestingly, a number of preclinical and clinical studies have indicated lack of full cross resistance between oxaliplatin based and irinotecan based treatment. Therefore, it is possible that certain mCRC patient subpopulations would benefit more from one drug combination rather than the other. To address this clinical problem there has been much focus on development and validation of predictive biomarkers for these three drugs. Here, we present a thorough review on the current status of predictive biomarkers for 5-FU, oxaliplatin and irinotecan treatment of mCRC patients. The overall conclusions were as follows: Several promising biomarker candidates were identified, notably thymidylate synthase for 5-FU, topoisomerase I for irinotecan and ERCC1 for oxaliplatin. However, these candidates warrant further analysis, where assay performance and clinical trial design should be in focus.
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Shiftwork and changes in health behaviors.
J. Occup. Environ. Med.
PUBLISHED: 12-14-2011
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We studied the associations between exposure to shiftwork and changes in health behaviors.
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A flucytosine-responsive Mbp1/Swi4-like protein, Mbs1, plays pleiotropic roles in antifungal drug resistance, stress response, and virulence of Cryptococcus neoformans.
Eukaryotic Cell
PUBLISHED: 11-11-2011
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Cryptococcosis, caused by the basidiomycetous fungus Cryptococcus neoformans, is responsible for more than 600,000 deaths annually in AIDS patients. Flucytosine is one of the most commonly used antifungal drugs for its treatment, but its resistance and regulatory mechanisms have never been investigated at the genome scale in C. neoformans. In the present study, we performed comparative transcriptome analysis by employing two-component system mutants (tco1? and tco2?) exhibiting opposing flucytosine susceptibility. As a result, a total of 177 flucytosine-responsive genes were identified, and many of them were found to be regulated by Tco1 or Tco2. Among these, we discovered an APSES-like transcription factor, Mbs1 (Mbp1- and Swi4-like protein 1). Expression analysis revealed that MBS1 was regulated in response to flucytosine in a Tco2/Hog1-dependent manner. Supporting this, C. neoformans with the deletion of MBS1 exhibited increased susceptibility to flucytosine. Intriguingly, Mbs1 played pleiotropic roles in diverse cellular processes of C. neoformans. Mbs1 positively regulated ergosterol biosynthesis and thereby affected polyene and azole drug susceptibility. Mbs1 was also involved in genotoxic and oxidative stress responses. Furthermore, Mbs1 promoted production of melanin and capsule and thereby was required for full virulence of C. neoformans. In conclusion, Mbs1 is considered to be a novel antifungal therapeutic target for treatment of cryptococcosis.
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Lack of independent prognostic and predictive value of centromere 17 copy number changes in breast cancer patients with known HER2 and TOP2A status.
Mol Oncol
PUBLISHED: 09-27-2011
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The clinical benefit of anthracyclines has been connected to HER2 status, TOP2A status and centromere 17 copy numbers (CEN-17). Data from a clinical trial randomizing patients to anthracyclines was used to assess whether the number of CEN-17 in breast cancers may predict incremental responsiveness to anthracyclines besides what is obtained when used relatively to TOP2A and HER2. As cut sections of paraffin-embedded tissue are prone to truncation of nuclei, strict definition of ploidy levels is lacking. We therefore used normal breast tissue to assist define ploidy levels in cut sections. Fluorescence in situ hybridization (FISH) with centromere 17 (CEN-17) and TOP2A was performed on 120 normal breast specimens. The diploid CEN-17 copy number was reduced from the expected two signals in whole nuclei to an average of 1.68 signals per nucleus in cut sections of normal breast. Ploidy levels determined in normal breast were applied to data on 767 patients with known HER2 and TOP2A status randomized to anthracyclines in the DBCG 89D trial. CEN-17 ploidy levels were in cut sections from the 767 breast cancer patients established as: Haploid: ?1.25 (10%), diploid: 1.26-2.09 (60%), triploid: 2.10-2.93 (21%), tetraploid: 2.94-3.77 (5%) or higher ploidy: ?3.78 (4%). Amplification of HER2 and deletion of TOP2A were frequently observed in tumors with a high ploidy level. In univariate analyses increasing ploidy was associated with decreased disease-free survival (DFS) (P=0.0001) and overall survival (OS) (P<0.0001). However, in multivariate analysis CEN-17 was not established as an independent prognostic factor and was neither a statistically significant predictor of benefit from CEF (Cyclophosphamide/Epirubicin/5-Fluorouracil) compared to CMF (Cyclophosphamide/Methotrexate/5-Fluorouracil) (P(Interaction) 0.39 for DFS and 0.67 for OS). In conclusion, CEN-17 levels do not independently from TOP2A/CEN-17 ratio identify breast cancer patients who achieve an incremental benefit from adjuvant anthracyclines.
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Cryptococcal titan cell formation is regulated by G-protein signaling in response to multiple stimuli.
Eukaryotic Cell
PUBLISHED: 08-05-2011
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The titan cell is a recently described morphological form of the pathogenic fungus Cryptococcus neoformans. Occurring during the earliest stages of lung infection, titan cells are 5 to 10 times larger than the normal yeast-like cells, thereby resisting engulfment by lung phagocytes and favoring the persistence of infection. These enlarged cells exhibit an altered capsule structure, a thickened cell wall, increased ploidy, and resistance to nitrosative and oxidative stresses. We demonstrate that two G-protein-coupled receptors are important for induction of the titan cell phenotype: the Ste3a pheromone receptor (in mating type a cells) and the Gpr5 protein. Both receptors control titan cell formation through elements of the cyclic AMP (cAMP)/protein kinase A (PKA) pathway. This conserved signaling pathway, in turn, mediates its effect on titan cells through the PKA-regulated Rim101 transcription factor. Additional downstream effectors required for titan cell formation include the G(1) cyclin Pcl103, the Rho104 GTPase, and two GTPase-activating proteins, Gap1 and Cnc1560. These observations support developing models in which the PKA signaling pathway coordinately regulates many virulence-associated phenotypes in diverse human pathogens.
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The effect of work-time influence on health and well-being: a quasi-experimental intervention study among eldercare workers.
Int Arch Occup Environ Health
PUBLISHED: 02-11-2011
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The aim of this study was to investigate the effect of work-time influence on stress and energy, work-family conflicts, lifestyle factors, and biomarkers of cardiovascular disease risk.
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Client-related work tasks and meaning of work: results from a longitudinal study among eldercare workers in Denmark.
Int Arch Occup Environ Health
PUBLISHED: 01-28-2011
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To investigate the association between the perception of client-related work tasks and the experience of meaning of work among eldercare workers in the Danish eldercare sector.
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Do guidelines recommending pharmacogenetic testing of psychiatric patients affect treatment costs and the use of healthcare services?
Scand J Public Health
PUBLISHED: 01-21-2011
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To identify the effects of local recommendations of pharmacogenetic testing in psychiatry with respect to treatment costs.
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Hrk1 plays both Hog1-dependent and -independent roles in controlling stress response and antifungal drug resistance in Cryptococcus neoformans.
PLoS ONE
PUBLISHED: 01-12-2011
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The HOG (High Osmolarity Glycerol response) pathway plays a central role in controlling stress response, ergosterol biosynthesis, virulence factor production, and differentiation of Cryptococcus neoformans, which causes fatal fungal meningoencephalitis. Recent transcriptome analysis of the HOG pathway discovered a Hog1-regulated gene (CNAG_00130.2), encoding a putative protein kinase orthologous to Rck1/2 in Saccharomyces cerevisiae and Srk1 in Schizosaccharomyces pombe. Its function is not known in C. neoformans. The present study functionally characterized the role of Hrk1 in C. neoformans. Northern blot analysis confirmed that HRK1 expression depends on the Hog1 MAPK. Similar to the hog1? mutant, the hrk1? mutant exhibited almost complete resistance to fludioxonil, which triggers glycerol biosynthesis via the HOG pathway. Supporting this, the hrk1? mutant showed reduced intracellular glycerol accumulation and swollen cell morphology in response to fludioxonil, further suggesting that Hrk1 works downstream of the HOG pathway. However, Hrk1 also appeared to have Hog1-independent functions. Mutation of HRK1 not only further increased osmosensitivity of the hog1? mutant, but also suppressed increased azole-resistance of the hog1? mutant in an Erg11-independent manner. Furthermore, unlike the hog1? mutant, Hrk1 was not involved in capsule biosynthesis. Hrk1 was slightly involved in melanin production but dispensable for virulence of C. neoformans. These findings suggest that Hrk1 plays both Hog1-dependent and -independent roles in stress and antifungal drug susceptibility and virulence factor production in C. neoformans. Particularly, the finding that inhibition of Hrk1 substantially increases azole drug susceptibility provides a novel strategy for combination antifungal therapy.
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The moderating effect of work-time influence on the effect of shift work: a prospective cohort study.
Int Arch Occup Environ Health
PUBLISHED: 05-18-2010
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To investigate whether work-time influence moderated the effect of shift work on psychological well-being measured as vitality, mental health, somatic stress symptoms, and disturbed sleep.
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Cryptococcal cell morphology affects host cell interactions and pathogenicity.
PLoS Pathog.
PUBLISHED: 05-12-2010
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Cryptococcus neoformans is a common life-threatening human fungal pathogen. The size of cryptococcal cells is typically 5 to 10 microm. Cell enlargement was observed in vivo, producing cells up to 100 microm. These morphological changes in cell size affected pathogenicity via reducing phagocytosis by host mononuclear cells, increasing resistance to oxidative and nitrosative stress, and correlated with reduced penetration of the central nervous system. Cell enlargement was stimulated by coinfection with strains of opposite mating type, and ste3aDelta pheromone receptor mutant strains had reduced cell enlargement. Finally, analysis of DNA content in this novel cell type revealed that these enlarged cells were polyploid, uninucleate, and produced daughter cells in vivo. These results describe a novel mechanism by which C. neoformans evades host phagocytosis to allow survival of a subset of the population at early stages of infection. Thus, morphological changes play unique and specialized roles during infection.
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Ste50 adaptor protein governs sexual differentiation of Cryptococcus neoformans via the pheromone-response MAPK signaling pathway.
Fungal Genet. Biol.
PUBLISHED: 05-11-2010
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The mitogen-activated protein kinase (MAPK) pathways control diverse cellular functions in pathogenic fungi, including sexual differentiation, stress response, and maintenance of cell wall integrity. Here we characterized a Cryptococcus neoformans gene, which is homologous to the yeast Ste50 that is known to play an important role in mating pheromone response and stress response as an adaptor protein to the Ste11 MAPK kinase kinase in Saccharomyces cerevisiae. The C. neoformans Ste50 was not involved in any of the stress responses or virulence factor production (capsule and melanin) that are controlled by the HOG and Ras/cAMP signaling pathways. However, Ste50 was required for mating in both serotype A and serotype D C. neoformans strains. The ste50? mutant was completely defective in cell-cell fusion and mating pheromone production. Double mutation of the STE50 gene blocked increased production of pheromone and the hyper-filamentation phenotype of cells deleted of the CRG1 gene, which encodes the RGS protein that negatively regulates pheromone responsive G-protein signaling via the MAPK pathway. Regardless of the presence of the basidiomycota-specific SH3 domains of Ste50 that are known to be required for full virulence of Ustilago maydis, Ste50 was dispensable for virulence of C. neoformans in a murine model of cryptococcosis. In conclusion, the Ste50 adaptor protein controls sexual differentiation of C. neoformans via the pheromone-responsive MAPK pathway but is not required for virulence.
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Mixed infections and In Vivo evolution in the human fungal pathogen Cryptococcus neoformans.
MBio
PUBLISHED: 03-24-2010
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Kochs postulates are criteria establishing a causal relationship between a microbe and a disease that lead to the assumption that diseases are caused by a single strain or its evolved forms. Cryptococcus neoformans is a life-threatening human fungal pathogen responsible for an estimated 1 million cases of cryptococcosis/year, predominantly meningoencephalitis. To assess the molecular diversity of clinical isolates and gain knowledge of C. neoformans biology in the host, we analyzed clinical cultures collected during the prospective CryptoA/D study. Using molecular analysis of unpurified isolates, we demonstrated that mixed infections in humans are more common than previously thought, occurring in almost 20% of patients diagnosed with cryptococcosis. These mixed infections are composed of different mating types, serotypes, and/or genotypes. We also identified genetically related haploid and diploid strains in the same patients. Experimental infections and quantitative PCR show that these ploidy changes can result from endoreplication (duplication of DNA content) and that shuttling between haploid and diploid states can occur, suggesting in vivo evolution. Thus, the concept of one strain/one infection does not hold true for C. neoformans and may apply to other environmentally acquired fungal pathogens. Furthermore, the possibility of mixed and/or evolving infections should be taken into account when developing therapeutic strategies against these pathogens.
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Amplification of ESR1 may predict resistance to adjuvant tamoxifen in postmenopausal patients with hormone receptor positive breast cancer.
Breast Cancer Res. Treat.
PUBLISHED: 02-10-2010
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The estrogen receptor (ER) is the target of tamoxifen, but endocrine therapies do not benefit all patients with ER positive tumors. We therefore hypothesized that copy number changes in the ESR1 gene, encoding ER, confer resistance. Within a consecutive series of ER positive, postmenopausal patients allocated to 5 years tamoxifen, we identified 61 patients with recurrence less than 4 years and 48 patients without recurrence at least 7 years after initiation of adjuvant tamoxifen. Archival tissue containing primary tumor was collected from 97 patients (89%). Tumor samples were analyzed for ESR1 copy number changes using FISH with a probe covering the ESR1 gene at 6q25 and a reference probe covering the centromere of chromosome 6. The assay was validated in a material of 120 normal breast samples. FISH analysis for ESR1 was successful in 91 patients (94%). Amplification (ratio ESR1/CEN-6 ? 2.0) was observed in 11 of 50 (22%) patients with early recurrence, compared to two of 41 (5%) patients without recurrence. The difference is statistically significant (P = 0.033). In both groups, two patients with ESR1 deletion (ratio ESR1/CEN-6 < 0.8) were identified. ESR1 amplification was significantly associated with poor disease-free survival (P = 0.0054) and overall survival (P = 0.0004). This pilot study supports our hypothesis that ESR1 amplification is associated with a poorer outcome following adjuvant treatment with tamoxifen in ER positive early breast cancer. This study also revealed the existence of ESR1 deletions. The prognostic and predictive impact of ESR1 copy number changes needs further exploration in clinical trials.
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Influence on working hours among shift workers and effects on sleep quality - An intervention study.
Appl Ergon
PUBLISHED: 02-01-2010
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The aim of the present intervention study was to examine if increased influence on working hours among shift workers led to better sleep quality. 391 employees were categorized into groups based on the performed activities: High (self-rostering), moderate (education and/or policy for working hours), and low intensity intervention (meetings and discussions) and reference. Sleep quality was assessed by Karolinska Sleep Questionnaire (KSQ) at baseline and follow-up (12 months). To elucidate the process of the intervention interviews were conducted. Influence on ones own working hours increased only in the high intensity group (p < 0.001). No effects of interventions on sleep quality were observed. Thus, sleep quality was not improved by increasing work time influence in the present group of Danish elder care workers. This was partly due to program failure (failed intervention), but may also be due to other factors such as few participants working night and few working full time.
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Molecular alterations in AKT1, AKT2 and AKT3 detected in breast and prostatic cancer by FISH.
Histopathology
PUBLISHED: 01-28-2010
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The AKT family is implicated in cancer progression. There are three mammalian AKT isoforms located on chromosomes 14, 19 and 1, respectively. The aim of the study was to investigate genetic alterations of AKT in breast and prostatic cancers using fluorescence in situ hybridization (FISH).
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The importance of individual preferences when evaluating the associations between working hours and indicators of health and well-being.
Appl Ergon
PUBLISHED: 01-06-2010
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Previous studies indicate that the effect of a given shift schedule may depend on individual factors. The aim of the present study was to investigate whether a misfit between individual preferences and actual working hours affected the association between working hours and self-reported indicators of health and well-being. The study population consisted of 173 female eldercare workers who mainly worked day or evening shifts. We combined self-reported questionnaire data on preferences with actual work schedules during a four-week period. The study showed that a misfit between preferences on one hand and "non-day work", "weekend work" or "only a few consecutive days off" on the other hand was associated with an increased dissatisfaction with working hours and/or an increase in the intention to leave the workplace due to ones working hours.
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HER2, TOP2A, and TIMP-1 and responsiveness to adjuvant anthracycline-containing chemotherapy in high-risk breast cancer patients.
J. Clin. Oncol.
PUBLISHED: 12-28-2009
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PURPOSE To evaluate whether the combination of HER2 with TIMP-1 (HT) or TOP2A with TIMP-1 (2T) more accurately identifies patients who benefit from cyclophosphamide, epirubicin, and fluorouracil (CEF) compared with cyclophosphamide, methotrexate, and fluorouracil (CMF) than these markers do when analyzed individually. PATIENTS AND METHODS The Danish Breast Cancer Cooperative Group (DBCG) 89D trial randomly assigned 980 high-risk Danish breast cancer patients to CMF or CEF. Archival tumor tissue was analyzed TIMP-1, and HER2-negative and TIMP-1 immunoreactive tumors were classified as HT nonresponsive and otherwise HT responsive. Similarly, the 2T panel was constructed by combining TOP2A and TIMP-1; tumors with normal TOP2A status and TIMP-1 immunoreactivity were classified as 2T-nonresponsive and otherwise 2T-responsive. Results In total, 623 tumors were available for analysis, of which 154 lacked TIMP-1 immunoreactivity, 188 were HER2 positive, and 139 had a TOP2A aberration. HT status was a statistically significant predictor of benefit from CEF compared with CMF (P(interaction) = .036 for invasive disease-free survival [IDFS] and .047 for overall survival [OS]). The 269 (43%) patients with a 2T-responsive profile had a significant reduction in IDFS events (adjusted hazard ratio, 0.48; 95% CI, 0.34 to 0.69; P < .001) and OS events (adjusted hazard ratio, 0.54; 95% CI, 0.38 to 0.77; P < .001). 2T status was a highly significant predictor of benefit from CEF compared with CMF (P(interaction) < .0001 for IDFS and .004 for OS). CONCLUSION The 2T profile is a more accurate predictor of incremental benefit from anthracycline-containing chemotherapy than HER2, TIMP-1, or TOP2A individually, and compared with these, 2T classifies a larger proportion of patients as sensitive to anthracyclines.
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Aberrations of ERBB2 and TOP2A genes in breast cancer.
Mol Oncol
PUBLISHED: 09-02-2009
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Copy number changes in TOP2A have frequently been linked to ERBB2 (HER2) amplified breast cancers. To study this relationship, copy number changes of ERBB2 and TOP2A were investigated by fluorescence in situ hybridization (FISH) in two cell lines; one characterized by having amplification of both genes and the other by having amplification of ERBB2 and deletion of TOP2A. The characteristics are compared to findings on paired ERBB2 and TOP2A data from 649 patients with invasive breast cancer from a previously published biomarker study. The physical localization of FISH signals in metaphase spreads from cell lines showed that simultaneous amplification is not a simple co-amplification of a whole amplicon containing both genes. Most gene signals are translocated to abnormal marker chromosomes. ERBB2 genes but not TOP2A genes are present in tandem amplicons, leading to a higher ERBB2 ratio. This observation was confirmed by patient FISH data: among 276 (43% of all patients) abnormal tumors, 67% had different ERBB2 and TOP2A status. ERBB2 amplification with normal TOP2A status was found in 36% of the abnormal tumors (15% of all patients). Simultaneous amplification of both genes was found in 28% of the abnormal tumors (12% of all patients) while TOP2A deletion and ERBB2 amplification was observed in 16% of the abnormal cases (8% of all patients). A small number of tumors had TOP2A amplification (4%) or deletion (6%) without simultaneous changes of the ERBB2 gene. ERBB2 deletion was also observed (5%) but only in tumors with simultaneous TOP2A deletion. The average gene/reference ratio was significantly different: 5.0 for TOP2A but 7.2 for ERBB2 in the amplified tumors (P<0.01). Amplification of the two genes may be caused by different mechanisms, leading to higher level of amplification for ERBB2 compared to TOP2A. In the majority of breast cancer patients, simultaneous aberration of ERBB2 and TOP2A is not explained by simple co-amplification.
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Differences between day and nonday workers in exposure to physical and psychosocial work factors in the Danish eldercare sector.
Scand J Work Environ Health
PUBLISHED: 03-12-2009
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The possible interaction between individual and occupational risk factors, the need for meaningful intervention, and the demand for valid shift work research make the accumulation of adverse exposures at certain times of the day of special relevance with respect to occupational health. The aim of the present study was therefore to examine whether there was a clustering of detrimental work factors among female eldercare workers in fixed evening or fixed night shifts when they are compared with workers in fixed day shifts.
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The predictive effect of fear-avoidance beliefs on low back pain among newly qualified health care workers with and without previous low back pain: a prospective cohort study.
BMC Musculoskelet Disord
PUBLISHED: 03-10-2009
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Health care workers have a high prevalence of low back pain (LBP). Although physical exposures in the working environment are linked to an increased risk of LBP, it has been suggested that individual coping strategies, for example fear-avoidance beliefs, could also be important in the development and maintenance of LBP. Accordingly, the main objective of this study was to examine (1) the association between physical work load and LBP, (2) the predictive effect of fear-avoidance beliefs on the development of LBP, and (3) the moderating effect of fear-avoidance beliefs on the association between physical work load and LBP among cases with and without previous LBP.
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Tissue context-activated telomerase in human epidermis correlates with little age-dependent telomere loss.
Biochim. Biophys. Acta
PUBLISHED: 02-06-2009
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Telomerase- and telomere length regulation in normal human tissues is still poorly understood. We show here that telomerase is expressed in the epidermis in situ independent of age but was repressed upon the passaging of keratinocytes in monolayer culture. However, when keratinocytes were grown in organotypic cultures (OTCs), telomerase was re-established, indicating that telomerase activity is not merely proliferation-associated but is regulated in a tissue context-dependent manner in human keratinocytes. While not inducible by growth factors, treatment with the histone deacetylation inhibitor FK228 restored telomerase activity in keratinocytes grown in monolayer cultures. Accordingly, CHIP analyses demonstrated an acetylated, active hTERT promoter in the epidermis in situ and in the epidermis of OTCs but a deacetylated, silenced hTERT promoter with subsequent propagation in monolayer culture suggesting that histone acetylation is part of the regulatory program to guarantee hTERT expression/telomerase activity in the epidermis. In agreement with the loss of telomerase activity, telomeres shortened during continuous propagation in monolayer culture by an average of approximately 70 base pairs (bp) per population doubling (pd). However, telomere erosion varied strongly between different keratinocyte strains and even between individual cells within the same culture, thereby arguing against a defined rate of telomere loss per replication cycle. In the epidermis in situ, as determined from early-passage keratinocytes and tissue sections from different age donors, we calculated a telomere loss of only approximately 25 bp per year. Since we determined the same rate for the non-regenerating melanocytes and dermal fibroblasts, our data suggest that in human epidermis telomerase is a protective mechanism against excessive telomere loss during the life-long regeneration.
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Evidence of a role for monocytes in dissemination and brain invasion by Cryptococcus neoformans.
Infect. Immun.
PUBLISHED: 01-24-2009
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The pathogenesis of cryptococcosis, including the events leading to the production of meningoencephalitis, is still largely unknown. Evidence of a transcellular passage of Cryptococcus neoformans across the blood-brain barrier (BBB) and subsequent BBB disruption exists, but the paracellular passage of free yeasts and the role of monocytes in yeast dissemination and brain invasion (Trojan horse method) remain uncertain. We used our model of disseminated cryptococcosis, in which crossing of the BBB starts 6 h after intravenous inoculation, to study paracellular passage of the BBB. We prepared bone marrow-derived monocytes (BMDM) infected in vitro with C. neoformans (BMDM yeasts) and free yeasts and measured fungal loads in tissues. (i) Spleen and lung CFU were >2-fold higher in mice treated with BMDM yeasts than in those treated with free yeasts for 1 and 24 h (P < 0.05), while brain CFU were increased (3.9 times) only at 24 h (P < 0.05). (ii) By comparing the kinetics of brain invasion in naïve mice and in mice with preestablished cryptococcosis, we found that CFU were lower in the latter case, except at 6 h, when CFU from mice inoculated with BMDM yeasts were comparable to those measured in naïve mice and 2.5-fold higher than those in mice with preestablished cryptococcosis who were inoculated with free yeasts. (iii) Late phagocyte depletion obtained by clodronate injection reduced disease severity and lowered the fungal burden by 40% in all organs studied. These results provide evidence for Trojan horse crossing of the BBB by C. neoformans, together with mechanisms involving free yeasts, and overall for a role of phagocytes in fungal dissemination.
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Topoisomerase 1(TOP1) gene copy number in stage III colorectal cancer patients and its relation to prognosis.
Mol Oncol
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A Topoisomerase 1 (Top1) poison is frequently included in the treatment regimens for metastatic colorectal cancer (mCRC). However, no predictive biomarkers for Top1 poisons are available. We here report a study on the TOP1 gene copy number in CRC patients and its association with patient prognosis and tumor cell proliferation.
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Pleiotropic roles of the Msi1-like protein Msl1 in Cryptococcus neoformans.
Eukaryotic Cell
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Msi1-like (MSIL) proteins contain WD40 motifs and have a pleiotropic cellular function as negative regulators of the Ras/cyclic AMP (cAMP) pathway and components of chromatin assembly factor 1 (CAF-1), yet they have not been studied in fungal pathogens. Here we identified and characterized an MSIL protein, Msl1, in Cryptococcus neoformans, which causes life-threatening meningoencephalitis in humans. Notably, Msl1 plays pleiotropic roles in C. neoformans in both cAMP-dependent and -independent manners largely independent of Ras. Msl1 negatively controls antioxidant melanin production and sexual differentiation, and this was repressed by the inhibition of the cAMP-signaling pathway. In contrast, Msl1 controls thermotolerance, diverse stress responses, and antifungal drug resistance in a Ras/cAMP-independent manner. Cac2, which is the second CAF-1 component, appears to play both redundant and distinct functions compared to the functions of Msl1. Msl1 is required for the full virulence of C. neoformans. Transcriptome analysis identified a group of Msl1-regulated genes, which include stress-related genes such as HSP12 and HSP78. In conclusion, this study demonstrates pleiotropic roles of Msl1 in the human fungal pathogen C. neoformans, providing insight into a potential novel antifungal therapeutic target.
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Cryptococcal genotype influences immunologic response and human clinical outcome after meningitis.
MBio
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In sub-Saharan Africa, cryptococcal meningitis (CM) continues to be a predominant cause of AIDS-related mortality. Understanding virulence and improving clinical treatments remain important. To characterize the role of the fungal strain genotype in clinical disease, we analyzed 140 Cryptococcus isolates from 111 Ugandans with AIDS and CM. Isolates consisted of 107 nonredundant Cryptococcus neoformans var. grubii strains and 8 C. neoformans var. grubii/neoformans hybrid strains. Multilocus sequence typing (MLST) was used to characterize genotypes, yielding 15 sequence types and 4 clonal clusters. The largest clonal cluster consisted of 74 isolates. The results of Burst and phylogenetic analysis suggested that the C. neoformans var. grubii strains could be separated into three nonredundant evolutionary groups (Burst group 1 to group 3). Patient mortality was differentially associated with the different evolutionary groups (P = 0.04), with the highest mortality observed among Burst group 1, Burst group 2, and hybrid strains. Compared to Burst group 3 strains, Burst group 1 strains were associated with higher mortality (P = 0.02), exhibited increased capsule shedding (P = 0.02), and elicited a more pronounced Th(2) response during ex vivo cytokine release assays with strain-specific capsule stimulation (P = 0.02). The results of these analyses suggest that cryptococcal strain variation can be an important determinant of human immune responses and mortality.
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Titan cell production enhances the virulence of Cryptococcus neoformans.
Infect. Immun.
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Infection with Cryptococcus neoformans begins when desiccated yeast cells or spores are inhaled and lodge in the alveoli of the lungs. A subset of cryptococcal cells in the lungs differentiate into enlarged cells, referred to as titan cells. Titan cells can be as large as 50 to 100 ?m in diameter and exhibit a number of features that may affect interactions with host immune defenses. To characterize the effect of titan cell formation on the host-pathogen interaction, we utilized a previously described C. neoformans mutant, the gpr4? gpr5? mutant, which has minimal titan cell production in vivo. The gpr4? gpr5? mutant strain had attenuated virulence, a lower CFU, and reduced dissemination compared to the wild-type strain. Titan cell production by the wild-type strain also resulted in increased eosinophil accumulation and decreased phagocytosis in the lungs compared to those with the gpr4? gpr5? mutant strain. Phagocytosed cryptococcal cells exhibited less viability than nonphagocytosed cells, which potentially explains the reduced cell survival and overall attenuation of virulence in the absence of titan cells. These data show that titan cell formation is a novel virulence factor in C. neoformans that promotes establishment of the initial pulmonary infection and plays a key role in disease progression.
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Implementation of self-rostering (the PRIO-project): effects on working hours, recovery, and health.
Scand J Work Environ Health
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The aim of this study was to (i) investigate the consequences of self-rostering for working hours, recovery, and health, and (ii) elucidate the mechanisms through which recovery and health are affected.
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Socially differentiated cardiac rehabilitation: can we improve referral, attendance and adherence among patients with first myocardial infarction?
Scand J Public Health
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The comprehensive cardiac rehabilitation (CR) programme after myocardial infarction (MI) improves quality of life and results in reduced cardiac mortality and recurrence of MI. Hospitals worldwide face problems with low participation rates in rehabilitation programmes. Inequality in recruitment and participation among low educated and socially vulnerable patients must be addressed to lower inequality in post-MI health. Our aim was to improve referral, attendance, and adherence rates among socially vulnerable patients by systematic screening and by offering a socially differentiated cardiac rehabilitation programme.
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ESR1 gene status correlates with estrogen receptor protein levels measured by ligand binding assay and immunohistochemistry.
Mol Oncol
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The Estrogen Receptor (ER) is an established predictive marker for the selection of adjuvant endocrine treatment in early breast cancer. During the 1990s Immunohistochemistry (IHC) replaced cytosol based assays for determination of ER status. This study examined the association between ER protein level determined by two different methods and ESR1 gene copy number. From 289 primary high-risk breast cancer patients, randomized in the Danish Breast Cancer Cooperative Group (DBCG) 77C trial, results from cytosolic ER levels were available from ligand binding assays. Archival tumor tissue was retrieved from 257 patients. ESR1/CEN-6 ratio was analyzed successfully by Fluorescence In Situ Hybridization (FISH) in 220 (86%) patients. ESR1 amplification (ESR1/CEN-6 ? 2.00) was observed in 23% of the patients and ESR1 deletion (ESR1/CEN-6 < 0.80) was observed in 32%. Further, we identified ESR1 gain (ratio ESR1/CEN-6 from 1.30 to 1.99) in 19% of the patients. A positive correlation of ESR1 FISH with both ER-cytosol and ER IHC was found (p < 0.0001). Amplification and gain of the ESR1 gene are associated with higher ER protein content measured by ligand binding assay and a more intense nuclear staining by IHC compared to tumors with normal ESR1 gene status. Major variations in ER measured by ligand binding assay and IHC are observed within all ESR1 copy number subgroups and other mechanisms than gene copy number seem to contribute to the ER protein content in the tumors.
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Titan cells confer protection from phagocytosis in Cryptococcus neoformans infections.
Eukaryotic Cell
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The human fungal pathogen Cryptococcus neoformans produces an enlarged "titan" cell morphology when exposed to the host pulmonary environment. Titan cells exhibit traits that promote survival in the host. Previous studies showed that titan cells are not phagocytosed and that increased titan cell production in the lungs results in reduced phagocytosis of cryptococcal cells by host immune cells. Here, the effect of titan cell production on host-pathogen interactions during early stages of pulmonary cryptococcosis was explored. The relationship between titan cell production and phagocytosis was found to be nonlinear; moderate increases in titan cell production resulted in profound decreases in phagocytosis, with significant differences occurring within the first 24 h of the infection. Not only were titan cells themselves protected from phagocytosis, but titan cell formation also conferred protection from phagocytosis to normal-size cryptococcal cells. Large particles introduced into the lungs were not phagocytosed, suggesting the large size of titan cells protects against phagocytosis. The presence of large particles was unable to protect smaller particles from phagocytosis, revealing that titan cell size alone is not sufficient to provide the observed cross-protection of normal-size cryptococcal cells. These data suggest that titan cells play a critical role in establishment of the pulmonary infection by promoting the survival of the entire population of cryptococcal cells.
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Increasing work-time influence: consequences for flexibility, variability, regularity and predictability.
Ergonomics
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This quasi-experimental study investigated how an intervention aiming at increasing eldercare workers influence on their working hours affected the flexibility, variability, regularity and predictability of the working hours. We used baseline (n = 296) and follow-up (n = 274) questionnaire data and interviews with intervention-group participants (n = 32). The work units in the intervention group designed their own intervention comprising either implementation of computerised self-scheduling (subgroup A), collection of information about the employees work-time preferences by questionnaires (subgroup B), or discussion of working hours (subgroup C). Only computerised self-scheduling changed the working hours and the way they were planned. These changes implied more flexible but less regular working hours and an experience of less predictability and less continuity in the care of clients and in the co-operation with colleagues. In subgroup B and C, the participants ended up discussing the potential consequences of more work-time influence without actually implementing any changes.
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A unique chromosomal rearrangement in the Cryptococcus neoformans var. grubii type strain enhances key phenotypes associated with virulence.
MBio
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The accumulation of genomic structural variation between closely related populations over time can lead to reproductive isolation and speciation. The fungal pathogen Cryptococcus is thought to have recently diversified, forming a species complex containing members with distinct morphologies, distributions, and pathologies of infection. We have investigated structural changes in genomic architecture such as inversions and translocations that distinguish the most pathogenic variety, Cryptococcus neoformans var. grubii, from the less clinically prevalent Cryptococcus neoformans var. neoformans and Cryptococcus gattii. Synteny analysis between the genomes of the three Cryptococcus species/varieties (strains H99, JEC21, and R265) reveals that C. neoformans var. grubii possesses surprisingly few unique genomic rearrangements. All but one are relatively small and are shared by all molecular subtypes of C. neoformans var. grubii. In contrast, the large translocation peculiar to the C. neoformans var. grubii type strain is found in all tested subcultures from multiple laboratories, suggesting that it has possessed this rearrangement since its isolation from a human clinical sample. Furthermore, we find that the translocation directly disrupts two genes. The first of these encodes a novel protein involved in metabolism of glucose at human body temperature and affects intracellular levels of trehalose. The second encodes a homeodomain-containing transcription factor that modulates melanin production. Both mutations would be predicted to increase pathogenicity; however, when recreated in an alternate genetic background, these mutations do not affect virulence in animal models. The type strain of C. neoformans var. grubii in which the majority of molecular studies have been performed is therefore atypical for carbon metabolism and key virulence attributes.
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Two cation transporters Ena1 and Nha1 cooperatively modulate ion homeostasis, antifungal drug resistance, and virulence of Cryptococcus neoformans via the HOG pathway.
Fungal Genet. Biol.
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Maintenance of cation homeostasis is essential for survival of all living organisms in their biological niches. It is also important for the survival of human pathogenic fungi in the host, where cation concentrations and pH will vary depending on different anatomical sites. However, the exact role of diverse cation transporters and ion channels in virulence of fungal pathogens remains elusive. In this study we functionally characterized ENA1 and NHA1, encoding a putative Na(+)/ATPase and Na(+)/H(+) antiporter, respectively, in Cryptococcus neoformans, a basidiomycete fungal pathogen which causes fatal meningoencephalitis. Expression of NHA1 and ENA1 is induced in response to salt and osmotic shock mainly in a Hog1-dependent manner. Phenotypic analysis of the ena1?, nha1?, and ena1?nha1? mutants revealed that Ena1 controls cellular levels of toxic cations, such as Na(+) and Li(+) whereas both Ena1 and Nha1 are important for controlling less toxic K(+) ions. Under alkaline conditions, Ena1 was highly induced and required for growth in the presence of low levels of Na(+) or K(+) salt and Nha1 played a role in survival under K(+) stress. In contrast, Nha1, but not Ena1, was essential for survival at acidic conditions (pH 4.5) under high K(+) stress. In addition, Ena1 and Nha1 were required for maintenance of plasma membrane potential and stability, which appeared to modulate antifungal drug susceptibility. Perturbation of ENA1 and NHA1 enhanced capsule production and melanin synthesis. However, Nha1 was dispensable for virulence of C. neoformans although Ena1 was essential. In conclusion, Ena1 and Nha1 play redundant and discrete roles in cation homeostasis, pH regulation, membrane potential, and virulence in C. neoformans, suggesting that these transporters could be novel antifungal drug targets for treatment of cryptococcosis.
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