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BACKGROUND: In 2020, during the COVID-19 pandemic, Médecins Sans Frontières (MSF) initiated three cycles of dihydroartemisin-piperaquine (DHA-PQ) mass drug administration (MDA) for children aged three months to 15 years within Bossangoa sub-prefecture, Central African Republic. Coverage, clinical impact, and community members perspectives were evaluated to inform the use of MDAs in humanitarian emergencies. METHODS: A household survey was undertaken after the MDA focusing on participation, recent illness among eligible children, and household satisfaction. Using routine surveillance data, the reduction during the MDA period compared to the same period of preceding two years in consultations, malaria diagnoses, malaria rapid diagnostic test (RDT) positivity in three MSF community healthcare facilities (HFs), and the reduction in severe malaria admissions at the regional hospital were estimated. Twenty-seven focus groups discussions (FGDs) with community members were conducted. RESULTS: Overall coverage based on the MDA card or verbal report was 94.3% (95% confidence interval (CI): 86.3-97.8%). Among participants of the household survey, 2.6% (95% CI 1.6-40.3%) of round 3 MDA participants experienced illness in the preceding four weeks compared to 30.6% (95% CI 22.1-40.8%) of MDA non-participants. One community HF experienced a 54.5% (95% CI 50.8-57.9) reduction in consultations, a 73.7% (95% CI 70.5-76.5) reduction in malaria diagnoses, and 42.9% (95% CI 36.0-49.0) reduction in the proportion of positive RDTs among children under five. A second community HF experienced an increase in consultations (+ 15.1% (- 23.3 to 7.5)) and stable malaria diagnoses (4.2% (3.9-11.6)). A third community HF experienced an increase in consultations (+ 41.1% (95% CI 51.2-31.8) and malaria diagnoses (+ 37.3% (95% CI 47.4-27.9)). There were a 25.2% (95% CI 2.0-42.8) reduction in hospital admissions with severe malaria among children under five from the MDA area. FGDs revealed community members perceived less illness among children because of the MDA, as well as fewer hospitalizations. Other indirect benefits such as reduced household expenditure on healthcare were also described. CONCLUSION: The MDA achieved high coverage and community acceptance. While some positive health impact was observed, it was resource intensive, particularly in this rural context. The priority for malaria control in humanitarian contexts should remain diagnosis and treatment. MDA may be additional tool where the context supports its implementation.
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Antimaláricos , Artemisininas , COVID-19 , Malária , Administração Massiva de Medicamentos , Humanos , Antimaláricos/uso terapêutico , Antimaláricos/administração & dosagem , Pré-Escolar , Lactente , Criança , Adolescente , COVID-19/epidemiologia , República Centro-Africana/epidemiologia , Artemisininas/uso terapêutico , Artemisininas/administração & dosagem , Administração Massiva de Medicamentos/estatística & dados numéricos , Feminino , Masculino , Malária/tratamento farmacológico , SARS-CoV-2 , Quinolinas/administração & dosagem , Quinolinas/uso terapêuticoRESUMO
The persistence of inadequate vaccination in crisis-affected settings raises concerns about decision making regarding vaccine selection, timing, location, and recipients. This review aims to describe the key features of childhood vaccination intervention design and planning in crisis-affected settings and investigate how the governance of childhood vaccination is defined, understood, and practised. We performed a scoping review of 193 peer-reviewed articles and grey literature on vaccination governance and service design and planning. We focused on 41 crises between 2010 and 2021. Following screening and data extraction, our analysis involved descriptive statistics and applying the governance analysis framework to code text excerpts, employing deductive and inductive approaches. Most documents related to active outbreaks in conflict-affected settings and to the mass delivery of polio, cholera, and measles vaccines. Information on vaccination modalities, target populations, vaccine sources, and funding was limited. We found various interpretations of governance, often implying hierarchical authority and regulation. Analysis of governance arrangements suggests a multi-actor yet fragmented governance structure, with inequitable actor participation, ineffective actor collaboration, and a lack of a shared strategic vision due to competing priorities and accountabilities. Better documentation of vaccination efforts during emergencies, including vaccination decision making, governance, and planning, is needed. We recommend empirical research within decision-making spaces.
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The burden of malaria is heavily concentrated in sub-Saharan Africa (SSA) where cases and deaths associated with COVID-19 are rising1. In response, countries are implementing societal measures aimed at curtailing transmission of SARS-CoV-22,3. Despite these measures, the COVID-19 epidemic could still result in millions of deaths as local health facilities become overwhelmed4. Advances in malaria control this century have been largely due to distribution of long-lasting insecticidal nets (LLINs)5, with many SSA countries having planned campaigns for 2020. In the present study, we use COVID-19 and malaria transmission models to estimate the impact of disruption of malaria prevention activities and other core health services under four different COVID-19 epidemic scenarios. If activities are halted, the malaria burden in 2020 could be more than double that of 2019. In Nigeria alone, reducing case management for 6 months and delaying LLIN campaigns could result in 81,000 (44,000-119,000) additional deaths. Mitigating these negative impacts is achievable, and LLIN distributions in particular should be prioritized alongside access to antimalarial treatments to prevent substantial malaria epidemics.
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Antimaláricos/uso terapêutico , Infecções por Coronavirus/epidemiologia , Malária/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Betacoronavirus/patogenicidade , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/parasitologia , Infecções por Coronavirus/virologia , Humanos , Inseticidas/uso terapêutico , Malária/complicações , Malária/parasitologia , Malária/virologia , Controle de Mosquitos , Pneumonia Viral/complicações , Pneumonia Viral/parasitologia , Pneumonia Viral/virologia , Saúde Pública , SARS-CoV-2RESUMO
BACKGROUND: Sulfadoxine-pyrimethamine (SP) is a cornerstone of malaria chemoprophylaxis and is considered for programmes in the Democratic Republic of Congo (DRC). However, SP efficacy is threatened by drug resistance, that is conferred by mutations in the dhfr and dhps genes. The World Health Organization has specified that intermittent preventive treatment for infants (IPTi) with SP should be implemented only if the prevalence of the dhps K540E mutation is under 50%. There are limited current data on the prevalence of resistance-conferring mutations available from Eastern DRC. The current study aimed to address this knowledge gap. METHODS: Dried blood-spot samples were collected from clinically suspected malaria patients [outpatient department (OPD)] and pregnant women attending antenatal care (ANC) in four sites in North and South Kivu, DRC. Quantitative PCR (qPCR) was performed on samples from individuals with positive and with negative rapid diagnostic test (RDT) results. Dhps K450E and A581G and dhfr I164L were assessed by nested PCR followed by allele-specific primer extension and detection by multiplex bead-based assays. RESULTS: Across populations, Plasmodium falciparum parasite prevalence was 47.9% (1160/2421) by RDT and 71.7 (1763/2421) by qPCR. Median parasite density measured by qPCR in RDT-negative qPCR-positive samples was very low with a median of 2.3 parasites/µL (IQR 0.5-25.2). Resistance genotyping was successfully performed in RDT-positive samples and RDT-negative/qPCR-positive samples with success rates of 86.2% (937/1086) and 55.5% (361/651), respectively. The presence of dhps K540E was high across sites (50.3-87.9%), with strong evidence for differences between sites (p < 0.001). Dhps A581G mutants were less prevalent (12.7-47.2%). The dhfr I164L mutation was found in one sample. CONCLUSIONS: The prevalence of the SP resistance marker dhps K540E exceeds 50% in all four study sites in North and South Kivu, DRC. K540E mutations regularly co-occurred with mutations in dhps A581G but not with the dhfr I164L mutation. The current results do not support implementation of IPTi with SP in the study area.
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Antimaláricos/farmacologia , Resistência a Medicamentos , Malária/prevenção & controle , Plasmodium/efeitos dos fármacos , Pirimetamina/farmacologia , Sulfadoxina/farmacologia , Adolescente , Biomarcadores/sangue , Quimioprevenção/estatística & dados numéricos , Criança , Pré-Escolar , República Democrática do Congo , Combinação de Medicamentos , Feminino , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
Epigenetic enzymes regulate higher-order chromatin architecture and cell-type specific gene expression. The ATPase BRG1 and the SWI/SNF chromatin remodeling complex are epigenetic enzymes that regulate chromatin accessibility during steady and transitional cell states. Experiments in mice show that the loss of BRG1 inhibits cellular reprogramming, while studies using human cells demonstrate that the overexpression of BRG1 enhances reprogramming. We hypothesized that the variation of SWI/SNF subunit expression in the human population would contribute to variability in the efficiency of induced pluripotent stem cells (iPSC) reprogramming. To examine the impact of an individual's sex, ancestry, and age on iPSC reprogramming, we created a novel sex and ancestry balanced cohort of 240 iPSC lines derived from human dermal fibroblasts (DF) from 80 heathy donors. We methodically assessed the reprogramming efficiency of each DF line and then quantified the individual and demographic-specific variations in SWI/SNF chromatin remodeling proteins and mRNA expression. We identified BRG1, BAF155, and BAF60a expression as strongly correlating with iPSC reprogramming efficiency. Additionally, we discovered that high efficiency iPSC reprograming is negatively correlated with donor age, positively correlated with African American descent, and uncorrelated with donor sex. These results show the variations in chromatin remodeling protein expression have a strong impact on iPSC reprogramming. Additionally, our cohort is unique in its large size, diversity, and focus on healthy donors. Consequently, this cohort can be a vital tool for researchers seeking to validate observational results from human population studies and perform detailed mechanistic studies in a controlled cell culture environment. Stem Cells 2018;36:1697-1708.
Assuntos
Reprogramação Celular/genética , Epigenômica/métodos , Expressão Gênica/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: The number of clinical cases of malaria is often recorded in resource constrained or conflict settings as a proxy for disease burden. Interpreting case count data in areas of humanitarian need is challenging due to uncertainties in population size caused by security concerns, resource constraints and population movement. Malaria prevalence in women visiting ante-natal care (ANC) clinics has the potential to be an easier and more accurate metric for malaria surveillance that is unbiased by population size if malaria testing is routinely conducted irrespective of symptoms. METHODS: A suite of distributed lag non-linear models was fitted to clinical incidence time-series data in children under 5 years and ANC prevalence data from health centres run by Médecins Sans Frontières in the Democratic Republic of Congo, which implement routine intermittent screening and treatment alongside intermittent preventative treatment in pregnancy. These statistical models enable the temporal relationship between the two metrics to be disentangled. RESULTS: There was a strong relationship between the ANC prevalence and clinical incidence suggesting that both can be used to describe current malaria endemicity. There was no evidence that ANC prevalence could predict future clinical incidence, though a change in clinical incidence was shown to influence ANC prevalence up to 3 months into the future. CONCLUSIONS: The results indicate that ANC prevalence may be a suitable metric for retrospective evaluations of the impact of malaria interventions and is a useful method for evaluating long-term malaria trends in resource constrained settings.
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Malária/epidemiologia , Cuidado Pré-Natal/estatística & dados numéricos , Pré-Escolar , República Democrática do Congo/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Modelos Estatísticos , Prevalência , Socorro em DesastresRESUMO
Hospital outbreaks of group A streptococcal (GAS) infection can be devastating and occasionally result in the death of previously well patients. Approximately one in ten cases of severe GAS infection is healthcare-associated. This guidance, produced by a multidisciplinary working group, provides an evidence-based systematic approach to the investigation of single cases or outbreaks of healthcare-associated GAS infection in acute care or maternity settings. The guideline recommends that all cases of GAS infection potentially acquired in hospital or through contact with healthcare or maternity services should be investigated. Healthcare workers, the environment, and other patients are possible sources of transmission. Screening of epidemiologically linked healthcare workers should be considered for healthcare-associated cases of GAS infection where no alternative source is readily identified. Communal facilities, such as baths, bidets and showers, should be cleaned and decontaminated between all patients especially on delivery suites, post-natal wards and other high risk areas. Continuous surveillance is required to identify outbreaks which arise over long periods of time. GAS isolates from in-patients, peri-partum patients, neonates, and post-operative wounds should be saved for six months to facilitate outbreak investigation. These guidelines do not cover diagnosis and treatment of GAS infection which should be discussed with an infection specialist.
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Infecção Hospitalar/prevenção & controle , Instalações de Saúde , Controle de Infecções/métodos , Infecções Estreptocócicas/prevenção & controle , Humanos , Reino UnidoRESUMO
BACKGROUND: Gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-beta-lactamase 1 (NDM-1) are potentially a major global health problem. We investigated the prevalence of NDM-1, in multidrug-resistant Enterobacteriaceae in India, Pakistan, and the UK. METHODS: Enterobacteriaceae isolates were studied from two major centres in India--Chennai (south India), Haryana (north India)--and those referred to the UK's national reference laboratory. Antibiotic susceptibilities were assessed, and the presence of the carbapenem resistance gene bla(NDM-1) was established by PCR. Isolates were typed by pulsed-field gel electrophoresis of XbaI-restricted genomic DNA. Plasmids were analysed by S1 nuclease digestion and PCR typing. Case data for UK patients were reviewed for evidence of travel and recent admission to hospitals in India or Pakistan. FINDINGS: We identified 44 isolates with NDM-1 in Chennai, 26 in Haryana, 37 in the UK, and 73 in other sites in India and Pakistan. NDM-1 was mostly found among Escherichia coli (36) and Klebsiella pneumoniae (111), which were highly resistant to all antibiotics except to tigecycline and colistin. K pneumoniae isolates from Haryana were clonal but NDM-1 producers from the UK and Chennai were clonally diverse. Most isolates carried the NDM-1 gene on plasmids: those from UK and Chennai were readily transferable whereas those from Haryana were not conjugative. Many of the UK NDM-1 positive patients had travelled to India or Pakistan within the past year, or had links with these countries. INTERPRETATION: The potential of NDM-1 to be a worldwide public health problem is great, and co-ordinated international surveillance is needed.
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Resistência Microbiana a Medicamentos/fisiologia , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/genética , Resistência Microbiana a Medicamentos/genética , Enterobacteriaceae/efeitos dos fármacos , Humanos , Índia/epidemiologia , Paquistão/epidemiologia , Plasmídeos/genética , Reação em Cadeia da Polimerase , Viagem , Reino Unido/epidemiologiaRESUMO
In cells lacking the histone methyltransferase Set2, initiation of RNA polymerase II transcription occurs inappropriately within the protein-coding regions of genes, rather than being restricted to the proximal promoter. It was previously reported that this "cryptic" transcription occurs preferentially in long genes, and in genes that are infrequently transcribed. Here, we mapped the transcripts produced in an S. cerevisiae strain lacking Set2, and applied rigorous statistical methods to identify sites of cryptic transcription at high resolution. We find that suppression of cryptic transcription occurs independent of gene length or transcriptional frequency. Our conclusions differ with those reported previously because we obtained a higher-resolution dataset, we accounted for the fact that gene length and transcriptional frequency are not independent variables, and we accounted for several ascertainment biases that make cryptic transcription easier to detect in long, infrequently transcribed genes. These new results and conclusions have implications for many commonly used genomic analysis approaches, and for the evolution of high-fidelity RNA polymerase II transcriptional initiation in eukaryotes.
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Histona Desacetilases/metabolismo , Metiltransferases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Transcrição Gênica , Algoritmos , Histona Desacetilases/genética , Metiltransferases/genética , Análise em Microsséries , Regiões Promotoras Genéticas , RNA/genética , RNA/metabolismo , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genéticaRESUMO
Histone lysine acetylation is a major mechanism by which cells regulate the structure and function of chromatin, and new sites of acetylation continue to be discovered. Here we identify and characterize histone H3K36 acetylation (H3K36ac). By mass spectrometric analyses of H3 purified from Tetrahymena thermophila and Saccharomyces cerevisiae (yeast), we find that H3K36 can be acetylated or methylated. Using an antibody specific to H3K36ac, we show that this modification is conserved in mammals. In yeast, genome-wide ChIP-chip experiments show that H3K36ac is localized predominantly to the promoters of RNA polymerase II-transcribed genes, a pattern inversely related to that of H3K36 methylation. The pattern of H3K36ac localization is similar to that of other sites of H3 acetylation, including H3K9ac and H3K14ac. Using histone acetyltransferase complexes purified from yeast, we show that the Gcn5-containing SAGA complex that regulates transcription specifically acetylates H3K36 in vitro. Deletion of GCN5 completely abolishes H3K36ac in vivo. These data expand our knowledge of the genomic targets of Gcn5, show H3K36ac is highly conserved, and raise the intriguing possibility that the transition between H3K36ac and H3K36me acts as an "acetyl/methyl switch" governing chromatin function along transcription units.
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Histonas/química , Acetilação , Sequência de Aminoácidos , Animais , Imunoprecipitação da Cromatina , Sequência Conservada , Histona Acetiltransferases/fisiologia , Humanos , Lisina , Metilação , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/fisiologia , Tetrahymena/químicaRESUMO
In yeast and other eukaryotes, the histone methyltransferase Set1 mediates methylation of lysine 4 on histone H3 (H3K4me). This modification marks the 5' end of transcribed genes in a 5'-to-3' tri- to di- to monomethyl gradient and promotes association of chromatin-remodeling and histone-modifying enzymes. Here we show that Ctk1, the serine 2 C-terminal domain (CTD) kinase for RNA polymerase II (RNAP II), regulates H3K4 methylation. We found that CTK1 deletion nearly abolished H3K4 monomethylation yet caused a significant increase in H3K4 di- and trimethylation. Both in individual genes and genome-wide, loss of CTK1 disrupted the H3K4 methylation patterns normally observed. H3K4me2 and H3K4me3 spread 3' into the bodies of genes, while H3K4 monomethylation was diminished. These effects were dependent on the catalytic activity of Ctk1 but are independent of Set2-mediated H3K36 methylation. Furthermore, these effects are not due to spurious transcription initiation in the bodies of genes, to changes in RNAP II occupancy, to changes in serine 5 CTD phosphorylation patterns, or to "transcriptional stress." These data show that Ctk1 acts to restrict the spread of H3K4 methylation through a mechanism that is independent of a general transcription defect. The evidence presented suggests that Ctk1 controls the maintenance of suppressive chromatin in the coding regions of genes by both promoting H3K36 methylation, which leads to histone deacetylation, and preventing the 3' spread of H3K4 trimethylation, a mark associated with transcriptional initiation.
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Genes Fúngicos , Histonas/metabolismo , Proteínas Quinases/metabolismo , RNA Polimerase II/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Região 5'-Flanqueadora , Cromatina/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Lisina/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Fosforilação , Proteínas Quinases/genética , RNA Polimerase II/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Sítio de Iniciação de TranscriçãoRESUMO
Set2p, which mediates histone H3 lysine 36 dimethylation (H3K36me2) in Saccharomyces cerevisiae, has been shown to associate with RNA polymerase II (RNAP II) at individual loci. Here, chromatin immunoprecipitation-microarray experiments normalized to general nucleosome occupancy reveal that nucleosomes within open reading frames (ORFs) and downstream noncoding chromatin were highly dimethylated at H3K36 and that Set2p activity begins at a stereotypic distance from the initiation of transcription genome-wide. H3K36me2 is scarce in regions upstream of divergently transcribed genes, telomeres, silenced mating loci, and regions transcribed by RNA polymerase III, providing evidence that the enzymatic activity of Set2p is restricted to its association with RNAP II. The presence of H3K36me2 within ORFs correlated with the "on" or "off" state of transcription, but the degree of H3K36 dimethylation within ORFs did not correlate with transcription frequency. This provides evidence that H3K36me2 is established during the initial instances of gene transcription, with subsequent transcription having at most a maintenance role. Accordingly, newly activated genes acquire H3K36me2 in a manner that does not correlate with gene transcript levels. Finally, nucleosomes dimethylated at H3K36 appear to be refractory to loss from highly transcribed chromatin. Thus, H3K36me2, which is highly conserved throughout eukaryotic evolution, provides a stable molecular mechanism for establishing chromatin context throughout the genome by distinguishing potential regulatory regions from transcribed chromatin.
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Cromatina/metabolismo , Genoma Fúngico , Histonas/metabolismo , Lisina/metabolismo , Metiltransferases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Cromatina/genética , Imunoprecipitação da Cromatina , Primers do DNA , Histonas/genética , Metilação , Metiltransferases/genética , Nucleossomos/genética , Nucleossomos/metabolismo , Fases de Leitura Aberta , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genéticaRESUMO
Whilst the international community's focus has been on the region most devastated by HIV/ AIDS, namely sub-Saharan Africa, India now appears on the brink of a significant AIDS epidemic. In thinking about the implications of HIV/AIDS, considerable attention was initially drawn to its clinical aspects. More recently, other dimensions of HIV, including economic, have been explored. The primary objective of this review is to elaborate on the major elements of the national and international economic research to data on HIV/AIDS, and to infer lessons from it, for India. It also examines the evidence on the aggregate and household-level economic impacts of HIV, the economic roots that drive its transmission and the methods economists use to assess the efficacy of alternative interventions to address HIV and AIDS. Available evidence suggests that whereas aggregate impacts may be limited, the adverse household-level economic implications of AIDS may be serious; public resources that are available for health are also likely to be put under strain. Paucity of economic research on HIV and AIDS relating to India is highlighted.
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Infecções por HIV/epidemiologia , Infecções por HIV/economia , Humanos , ÍndiaRESUMO
The identification of nuclease-hypersensitive sites in an active globin gene and in the 5' regions of fruit fly heat shock genes first suggested that chromatin changes accompany gene regulation in vivo. Here we present evidence that the basic repeating units of eukaryotic chromatin, nucleosomes, are depleted from active regulatory elements throughout the Saccharomyces cerevisiae genome in vivo. We found that during rapid mitotic growth, the level of nucleosome occupancy is inversely proportional to the transcriptional initiation rate at the promoter. We also observed a partial loss of histone H3 and H4 tetramers from the coding regions of the most heavily transcribed genes. Alterations in the global transcriptional program caused by heat shock or a change in carbon source resulted in an increased nucleosome occupancy at repressed promoters, and a decreased nucleosome occupancy at promoters that became active. Nuclease-hypersensitive sites occur in species from yeast to humans and result from chromatin perturbation. Given the conservation of sequence and function among components of both chromatin and the transcriptional machinery, nucleosome depletion at promoters may be a fundamental feature of eukaryotic transcriptional regulation.