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Four incorrect figure citations in this Letter have been corrected online.
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The inversion of inhomogeneous physical states has great technological importance; for example, active noise reduction relies on the emission of an inverted sound wave that interferes destructively with the noise of the emitter1, and inverting the evolution of a spin system by using a magnetic-field pulse enables magnetic resonance tomography2. In contrast to these examples, inversion of a distribution of ferromagnetic or ferroelectric domains within a material is surprisingly difficult: field poling creates a single-domain state, and piece-by-piece inversion using a scanning tip is impractical. Here we report inversion of entire ferromagnetic and ferroelectric domain patterns in the magnetoelectric material Co3TeO6 and the multiferroic material Mn2GeO4, respectively. In these materials, an applied magnetic field reverses the magnetization or polarization, respectively, of each domain, but leaves the domain pattern intact. Landau theory indicates that this type of magnetoelectric inversion is universal across materials that exhibit complex ordering, with one order parameter holding the memory of the domain structure and another setting its overall sign. Domain-pattern inversion is only one example of a previously unnoticed effect in systems such as multiferroics, in which several order parameters are available for combination. Exploring these effects could therefore advance multiferroics towards new levels of functionality.
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BACKGROUND: Hypotrichosis simplex of the scalp (HSS) is characterized by progressive loss of scalp hair that results in almost complete baldness at a young age. HSS is often caused by dominant nonsense mutations in CDSN encoding corneodesmosin, leading to the formation of an amyloid-like material, which interferes with normal hair follicle cycle. OBJECTIVES: As gentamicin has been shown to mediate ribosomal read-through, we aimed to ascertain its therapeutic efficacy in a small series of patients carrying a recurrent mutation in CDSN . METHODS: We used a green fluorescence reporter assay system, confocal microscopy and Western blot analysis to ascertain in vitro the ability of gentamicin to induce translational read-through across a causative CDSN mutation. RESULTS: Using a reporter assay, we initially showed that gentamicin induces read-through activity across an HSS-causing nonsense mutation. Gentamicin was further shown to rescue corneodesmosin translation in primary keratinocytes obtained from a patient with HSS. To validate the in vitro data, we conducted a pilot clinical trial where the scalp of four patients was treated topically with gentamicin for 6 months, demonstrating significant improvement as ascertained by the Severity of Alopecia Tool score. CONCLUSIONS: Our findings indicate that topical gentamicin should be considered as a potential therapeutic modality in HSS. What's already known about this topic? Hypotrichosis simplex of the scalp (HSS) is caused by nonsense mutations in CDSN encoding corneodesmosin. The mutant corneodesmosin has been hypothesized to be toxic to the hair follicles, leading to hypotrichosis. Disorders caused by nonsense mutations are amenable to ribosomal read-through using gentamicin. What does this study add? Gentamicin enhanced read-through activity and promoted full-length corneodesmosin synthesis in primary keratinocytes derived from patients carrying a nonsense mutation in CDSN. Topical treatment with gentamicin was found to rescue the hypotrichosis phenotype partially in four patients with HSS. What is the translational message? Topical gentamicin should be considered as a potential treatment for HSS.
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Hipotricose , Couro Cabeludo , Gentamicinas , Glicoproteínas/genética , Humanos , Hipotricose/tratamento farmacológico , Hipotricose/genética , Peptídeos e Proteínas de Sinalização Intercelular , LinhagemRESUMO
BACKGROUND: The whale shark (Rhincodon typus) has by far the largest body size of any elasmobranch (shark or ray) species. Therefore, it is also the largest extant species of the paraphyletic assemblage commonly referred to as fishes. As both a phenotypic extreme and a member of the group Chondrichthyes - the sister group to the remaining gnathostomes, which includes all tetrapods and therefore also humans - its genome is of substantial comparative interest. Whale sharks are also listed as an endangered species on the International Union for Conservation of Nature's Red List of threatened species and are of growing popularity as both a target of ecotourism and as a charismatic conservation ambassador for the pelagic ecosystem. A genome map for this species would aid in defining effective conservation units and understanding global population structure. RESULTS: We characterised the nuclear genome of the whale shark using next generation sequencing (454, Illumina) and de novo assembly and annotation methods, based on material collected from the Georgia Aquarium. The data set consisted of 878,654,233 reads, which yielded a draft assembly of 1,213,200 contigs and 997,976 scaffolds. The estimated genome size was 3.44Gb. As expected, the proteome of the whale shark was most closely related to the only other complete genome of a cartilaginous fish, the holocephalan elephant shark. The whale shark contained a novel Toll-like-receptor (TLR) protein with sequence similarity to both the TLR4 and TLR13 proteins of mammals and TLR21 of teleosts. The data are publicly available on GenBank, FigShare, and from the NCBI Short Read Archive under accession number SRP044374. CONCLUSIONS: This represents the first shotgun elasmobranch genome and will aid studies of molecular systematics, biogeography, genetic differentiation, and conservation genetics in this and other shark species, as well as providing comparative data for studies of evolutionary biology and immunology across the jawed vertebrate lineages.
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Genômica , Análise de Sequência , Tubarões/genética , Animais , Conservação dos Recursos Naturais , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Homologia de Sequência do Ácido NucleicoRESUMO
We determined the prevalence of anti-hepatitis B surface antibodies (anti-HBs) among children and adolescents vaccinated for hepatitis B virus in infancy as part of the routine vaccination programme. A representative serum sample of the Israeli population age 0-19 was tested. In a separate pilot study, a booster dose of hepatitis B vaccine was administered to 31 candidates for national service, who were fully vaccinated in infancy and tested negative for hepatitis B surface antibodies at age 17-19 years and anti-HBs antibodies were assessed 8 weeks later. Of the 1273 samples tested, 631 (49·6%) were positive to anti-HBs antibodies. Seropositivity rates were 89·5% among infants aged 6-12 months and declined significantly with age to 20·7% at age 19 years. No differences in seropositivity rates were observed between Jews and Arabs, males and females and those born in Israel and in other countries. Seroconversion rate among the 31 individuals who received a booster dose was 90·3% (95% CI: 75·1-96·6%). We recommend a booster dose for healthcare personnel before starting to work at the health care facility.
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Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Imunização Secundária , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Hepatite B/epidemiologia , Hepatite B/virologia , Vírus da Hepatite B/imunologia , Humanos , Lactente , Recém-Nascido , Israel/epidemiologia , Masculino , Projetos Piloto , Prevalência , Estudos Soroepidemiológicos , Adulto JovemRESUMO
BACKGROUND: Polio eradication is an extraordinary globally coordinated health program in terms of its magnitude and reach, leading to the elimination of wild poliovirus (WPV) in most parts of the world. In 2013, a silent outbreak of WPV was detected in Israel, a country using an inactivated polio vaccine (IPV) exclusively since 2005. The outbreak was detected using environmental surveillance (ES) of sewage reservoirs. Stool surveys indicated the outbreak to be restricted mainly to children under the age of 10 in the Bedouin population of southern Israel. In order to curtail the outbreak, a nationwide vaccination campaign using oral polio vaccine (OPV) was conducted, targeting all children under 10. METHODS: A transmission model, fitted to the results of the stool surveys, with additional conditions set by the ES measurements, was used to evaluate the prevalence of WPV in Bedouin children and the effectiveness of the vaccination campaign. Employing the parameter estimates of the model fitting, the model was used to investigate the effect of alternative timings, coverages and dosages of the OPV campaign on the outcome of the outbreak. RESULTS: The mean estimate for the mean reproductive number was 1.77 (95 % credible interval, 1.46-2.30). With seasonal variation, the reproductive number maximum range was between zero and six. The mean estimate for the mean infectious periods was 16.8 (8.6-24.9) days. The modeling indicates the OPV campaign was effective in curtailing the outbreak. The mean estimate for the attack rate in Bedouin children under 10 at the end of 2014 was 42 % (22-65 %), whereas without the campaign the mean projected attack rate was 57 % (35-74 %). The campaign also likely shortened the duration of the outbreak by a mean estimate of 309 (2-846) days. A faster initiation of the OPV campaign could have reduced the incidence of WPV even if a lower coverage was reached, at the risk of prolonging the outbreak. CONCLUSIONS: OPV campaigns are essential for interrupting WPV transmission, even in a developed country setting with a high coverage of IPV. In this setting, establishing ES of WPV circulation is particularly crucial for early detection and containment of an outbreak.
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Poliomielite/epidemiologia , Poliomielite/transmissão , Vacina Antipólio Oral/administração & dosagem , Vacinação/métodos , Árabes/estatística & dados numéricos , Criança , Pré-Escolar , Surtos de Doenças/prevenção & controle , Humanos , Lactente , Israel/epidemiologia , Modelos Estatísticos , Poliomielite/prevenção & controle , Vacina Antipólio de Vírus Inativado/administração & dosagem , Vacinação/estatística & dados numéricosRESUMO
Chlamydia psittaci is an obligate intracellular bacterium that can cause significant disease among a broad range of hosts. In humans, this organism may cause psittacosis, a respiratory disease that can spread to involve multiple organs, and in rare untreated cases may be fatal. There are ten known genotypes based on sequencing the major outer-membrane protein gene, ompA, of C. psittaci. Each genotype has overlapping host preferences and virulence characteristics. Recent studies have compared C. psittaci among other members of the Chlamydiaceae family and showed that this species frequently switches hosts and has undergone multiple genomic rearrangements. In this study, we sequenced five genomes of C. psittaci strains representing four genotypes, A, B, D and E. Due to the known association of the type III secretion system (T3SS) and polymorphic outer-membrane proteins (Pmps) with host tropism and virulence potential, we performed a comparative analysis of these elements among these five strains along with a representative genome from each of the remaining six genotypes previously sequenced. We found significant genetic variation in the Pmps and tbl3SS genes that may partially explain differences noted in C. psittaci host infection and disease.
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Proteínas da Membrana Bacteriana Externa/genética , Chlamydophila psittaci/genética , Variação Genética , Genoma Bacteriano , Sistemas de Secreção Tipo III/genética , Biologia Computacional , DNA Bacteriano/química , DNA Bacteriano/genética , Genótipo , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
Microorganisms may colonize needleless connectors (NCs) on intravascular catheters, forming biofilms and predisposing patients to catheter-associated infection (CAI). Standard and silver-coated NCs were collected from catheterized intensive care unit patients to characterize biofilm formation using culture-dependent and culture-independent methods and to investigate the associations between NC usage and biofilm characteristics. Viable microorganisms were detected by plate counts from 46% of standard NCs and 59% of silver-coated NCs (P=0.11). There were no significant associations (P>0.05, chi-square test) between catheter type, side of catheter placement, number of catheter lumens, site of catheter placement, or NC placement duration and positive NC findings. There was an association (P=0.04, chi-square test) between infusion type and positive findings for standard NCs. Viable microorganisms exhibiting intracellular esterase activity were detected on >90% of both NC types (P=0.751), suggesting that a large percentage of organisms were not culturable using the conditions provided in this study. Amplification of the 16S rRNA gene from selected NCs provided a substantially larger number of operational taxonomic units per NC than did plate counts (26 to 43 versus 1 to 4 operational taxonomic units/NC, respectively), suggesting that culture-dependent methods may substantially underestimate microbial diversity on NCs. NC bacterial communities were clustered by patient and venous access type and may reflect the composition of the patient's local microbiome but also may contain organisms from the health care environment. NCs provide a portal of entry for a wide diversity of opportunistic pathogens to colonize the catheter lumen, forming a biofilm and increasing the potential for CAI, highlighting the importance of catheter maintenance practices to reduce microbial contamination.
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Bactérias/isolamento & purificação , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Cateteres Venosos Centrais/microbiologia , Desinfetantes/farmacologia , Prata/farmacologia , Bactérias/classificação , Bactérias/genética , Biodiversidade , Análise por Conglomerados , Contagem de Colônia Microbiana , Hospitais , Humanos , Unidades de Terapia Intensiva , Filogenia , RNA Ribossômico 16S/genéticaRESUMO
Exserohilum rostratum was the cause of most cases of fungal meningitis and other infections associated with the injection of contaminated methylprednisolone acetate produced by the New England Compounding Center (NECC). Until this outbreak, very few human cases of Exserohilum infection had been reported, and very little was known about this dematiaceous fungus, which usually infects plants. Here, we report using whole-genome sequencing (WGS) for the detection of single nucleotide polymorphisms (SNPs) and phylogenetic analysis to investigate the molecular origin of the outbreak using 22 isolates of E. rostratum retrieved from 19 case patients with meningitis or epidural/spinal abscesses, 6 isolates from contaminated NECC vials, and 7 isolates unrelated to the outbreak. Our analysis indicates that all 28 isolates associated with the outbreak had nearly identical genomes of 33.8 Mb. A total of 8 SNPs were detected among the outbreak genomes, with no more than 2 SNPs separating any 2 of the 28 genomes. The outbreak genomes were separated from the next most closely related control strain by â¼136,000 SNPs. We also observed significant genomic variability among strains unrelated to the outbreak, which may suggest the possibility of cryptic speciation in E. rostratum.
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Ascomicetos/classificação , Ascomicetos/genética , Surtos de Doenças , Genoma Fúngico , Meningite Fúngica/epidemiologia , Micoses/epidemiologia , Ascomicetos/isolamento & purificação , Análise por Conglomerados , Humanos , Meningite Fúngica/microbiologia , Epidemiologia Molecular , Dados de Sequência Molecular , Tipagem Molecular , Técnicas de Tipagem Micológica , Micoses/microbiologia , New England , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNARESUMO
Zoonotic and vector-borne pathogens have comprised a significant component of emerging human infections in recent decades, and bats are increasingly recognized as reservoirs for many of these disease agents. To identify novel pathogens associated with bats, we screened tissues of bats collected in Kenya. Virus isolates were identified by next generation sequencing of viral nucleic acid preparations from the infected cell culture supernatant and characterized. Here we report the identification of Fikirini rhabdovirus, a novel rhabdovirus isolated from a bat, Hipposideros vittatus, captured along the Kenyan coast.
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Quirópteros/virologia , Infecções por Rhabdoviridae/veterinária , Rhabdoviridae/genética , Animais , Reservatórios de Doenças/virologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Quênia , Fígado/virologia , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Rhabdoviridae/classificação , Rhabdoviridae/isolamento & purificação , Infecções por Rhabdoviridae/virologia , Análise de Sequência de DNA/métodosRESUMO
The semiconductor field-effect platform represents a powerful tool for detecting the adsorption and binding of charged macromolecules with direct electrical readout. In this work, a capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensor consisting of an Al-p-Si-SiO2 structure has been applied for real-time in situ electrical monitoring of the layer-by-layer formation of polyelectrolyte (PE) multilayers (PEM). The PEMs were deposited directly onto the SiO2 surface without any precursor layer or drying procedures. Anionic poly(sodium 4-styrene sulfonate) and cationic weak polyelectrolyte poly(allylamine hydrochloride) have been chosen as a model system. The effect of the ionic strength of the solution, polyelectrolyte concentration, number and polarity of the PE layers on the characteristics of the PEM-modified EIS sensors have been studied by means of capacitance-voltage and constant-capacitance methods. In addition, the thickness, surface morphology, roughness and wettabilityof the PE mono- and multilayers have been characterised by ellipsometry, atomic force microscopy and water contact-angle methods, respectively. To explain potential oscillations on the gate surface and signal behaviour of the capacitive field-effect EIS sensor modified with a PEM, a simplified electrostatic model that takes into account the reduced electrostatic screening of PE charges by mobile ions within the PEM has been proposed and discussed.
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BACKGROUND: Cowpox virus is an Orthopoxvirus that can cause infections in humans and a variety of animals. Infections occur in Eurasia; infections in humans and animals have not been reported in the United States. This report describes the occurrence of the first known human case of laboratory-acquired cowpox virus infection in the United States and the ensuing investigation. METHODS: The patient and laboratory personnel were interviewed, and laboratory activities were reviewed. Real-time polymerase chain reaction (PCR) and serologic assays were used to test the patient's specimens. PCR assays were used to test specimens obtained during the investigation. RESULTS: A specimen from the patient's lesion tested positive for cowpox virus DNA. Genome sequencing revealed a recombinant region consistent with a strain of cowpox virus stored in the research laboratory's freezer. Cowpox virus contamination was detected in 6 additional laboratory stocks of viruses. Orthopoxvirus DNA was present in 3 of 20 environmental swabs taken from laboratory surfaces. CONCLUSIONS: The handling of contaminated reagents or contact with contaminated surfaces was likely the mode of transmission. Delays in recognition and diagnosis of this infection in a laboratory researcher underscore the importance of a thorough patient history-including occupational information-and laboratory testing in facilitating a prompt investigation and application of control and remediation measures.
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Vírus da Varíola Bovina/isolamento & purificação , Varíola Bovina/virologia , DNA Viral/isolamento & purificação , Transmissão de Doença Infecciosa do Paciente para o Profissional , Infecção Laboratorial/virologia , Pessoal de Laboratório , Varíola Bovina/epidemiologia , Varíola Bovina/transmissão , Vírus da Varíola Bovina/genética , Contaminação por DNA , DNA Viral/genética , Humanos , Infecção Laboratorial/epidemiologia , Infecção Laboratorial/transmissão , Estados Unidos/epidemiologiaRESUMO
RNase III is a key enzyme in the pathways of RNA degradation and processing in bacteria and has been suggested as a global regulator of antibiotic production in Streptomyces coelicolor. Using RNA-Seq, we have examined the transcriptomes of S. coelicolor M145 and an RNase III (rnc)-null mutant of that strain. RNA preparations with reduced levels of structural RNAs were prepared by subtractive hybridization prior to RNA-Seq analysis. We initially identified 7,800 transcripts of known and putative protein-coding genes in M145 and the null mutant, JSE1880, along with transcripts of 21 rRNA genes and 65 tRNA genes. Approximately 3,100 of the protein-coding transcripts were categorized as low-abundance transcripts. For further analysis, we selected those transcripts of known and putative protein-coding genes whose levels changed by ≥ 2-fold between the two S. coelicolor strains and organized those transcripts into 16 functional categories. We refined our analysis by performing RNA immunoprecipitation of the mRNA preparation from JSE1880 using a mutant RNase III protein that binds to transcripts but does not cleave them. This analysis identified ca. 800 transcripts that were enriched in the RNA immunoprecipitates, including 28 transcripts whose levels also changed by ≥ 2-fold in the RNA-Seq analysis. We compare our results with those obtained by microarray analysis of the S. coelicolor transcriptome and with studies describing the characterization of small noncoding RNAs. We have also used the RNA immunoprecipitation results to identify new substrates for RNase III cleavage.
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RNA Bacteriano/metabolismo , Ribonuclease III/metabolismo , Streptomyces coelicolor/metabolismo , Antibacterianos/metabolismo , Sequência de Bases , DNA Complementar , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Imunoprecipitação , Conformação de Ácido Nucleico , RNA Bacteriano/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonuclease III/genética , Streptomyces coelicolor/genéticaRESUMO
Background: With cancer as one of the leading causes of death worldwide, accurate primary tumor type prediction is critical in identifying genetic factors that can inhibit or slow tumor progression. There have been efforts to categorize primary tumor types with gene expression data using machine learning, and more recently with deep learning, in the last several years. Methods: In this paper, we developed four 1-dimensional (1D) Convolutional Neural Network (CNN) models to classify RNA-seq count data as one of 17 highly represented primary tumor types or 32 primary tumor types regardless of imbalanced representation. Additionally, we adapted the models to take as input either all Ensembl genes (60,483) or protein coding genes only (19,758). Unlike previous work, we avoided selection bias by not filtering genes based on expression values. RNA-seq count data expressed as FPKM-UQ of 9,025 and 10,940 samples from The Cancer Genome Atlas (TCGA) were downloaded from the Genomic Data Commons (GDC) corresponding to 17 and 32 primary tumor types respectively for training and validating the models. Results: All 4 1D-CNN models had an overall accuracy of 94.7% to 97.6% on the test dataset. Further evaluation indicates that the models with protein coding genes only as features performed with better accuracy compared to the models with all Ensembl genes for both 17 and 32 primary tumor types. For all models, the accuracy by primary tumor type was above 80% for most primary tumor types. Conclusions: We packaged all 4 models as a Python-based deep learning classification tool called TULIP (TUmor CLassIfication Predictor) for performing quality control on primary tumor samples and characterizing cancer samples of unknown tumor type. Further optimization of the models is needed to improve the accuracy of certain primary tumor types.
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PURPOSE: Neurogenic detrusor overactivity (NDO) is common in patients who suffer from multiple sclerosis (MS). When the usual pharmacological treatment fails, botulinum toxin type A (BTX-A) injections can be proposed. The safety and efficacy of this treatment are already well known, but only a few studies focus on its use in patients with MS. MATERIALS AND METHODS: Seventy-one patients with MS underwent their first BTX-A injection for refractory NDO. They had clinical and urodynamic cystometry assessment before and three months after injection. The patients were divided in three groups according to treatment efficacy: full success (total urinary continence, no overactive detrusor), improvement, or total failure (urge incontinence and overactive detrusor). RESULTS: 77% of the patients had clinical improvement or full success of the treatment with a reduction of their urgency and incontinence. Significant urodynamic improvement after treatment was shown on different parameters: volume at first involuntary bladder contraction (p = 0.0000001), maximum cystometric capacity (p = 0.0035), maximum detrusor pressure (p = 0.0000001). 46% of the patients were in the "full success" group. 31% of the patients had a partial improvement. 23% of the patients had no efficacy of the treatment. Duration of MS was a predictive factor of treatment failure (p = 0.015). CONCLUSIONS: Despite that a full success was obtained in 46% of the cases, BTX-A injection therapy failed to treat refractory NDO in 23% of patients suffering from MS. Duration of the disease was a predictive factor for an inefficient treatment. The injection therapy should be considered as soon as oral anti cholinergic drugs fail to reduce NDO.
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Toxinas Botulínicas Tipo A/administração & dosagem , Esclerose Múltipla/complicações , Fármacos Neuromusculares/administração & dosagem , Bexiga Urinaria Neurogênica/tratamento farmacológico , Bexiga Urinária Hiperativa/tratamento farmacológico , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Bexiga Urinaria Neurogênica/complicações , Bexiga Urinária Hiperativa/complicações , UrodinâmicaRESUMO
INTRODUCTION: The bladder deformations observed in the neurogenic bladders are frequent, particularly in the "upper motor neuron" bladder type (paraplegia, multiple sclerosis). We wanted to verify the predictive factors of such damage and particularly, if the urodynamic typology intervened in their genesis by using the model of cauda equina syndrome and conus medullaris lesions. PATIENTS AND METHODS: We have studied retrospectively the presence of cystographic bladder deformations at patients with neurogenic bladder due to cauda equina syndrome or conus medullaris lesion according to their urodynamic status: either overactive or acontractile detrusor. RESULTS: Of 68 patients, (mean age 47.2 years), 34 had an overactive and 34 an acontractile detrusor. The presence of bladder deformations was associated with an overactive detrusor (p=0.04). However, 50% of the patients with acontractile detrusor had bladder deformations, and those deformations were associated with male sex, and this excluding urologic obstruction. CONCLUSION: This study demonstrates the existence of bladder deformations in the hypoactive lower motor neuron neurogenic bladder type. If the bladder deformations seem more frequent in the overactive neurogenic bladder type, their specific and repeated search is also necessary during the follow-up of the lower motor neuron neurogenic bladder type.
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Polirradiculopatia/complicações , Compressão da Medula Espinal/complicações , Bexiga Urinaria Neurogênica/complicações , Bexiga Urinária/anormalidades , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
Cancer risk from galactic cosmic radiation exposure is considered a potential "showstopper" for a manned mission to Mars. Calculating the actual risks confronted by spaceflight crews is complicated by our limited understanding of the carcinogenic effects of high-charge, high-energy (HZE) ions, a radiation type for which no human exposure data exist. Using a mouse model of genetic diversity, we find that the histotype spectrum of HZE ion-induced tumors is similar to the spectra of spontaneous and γ-ray-induced tumors and that the genomic loci controlling susceptibilities overlap between groups for some tumor types. Where it occurs, this overlap indicates shared tumorigenesis mechanisms regardless of the type of radiation exposure and supports the use of human epidemiological data from γ-ray exposures to predict cancer risks from galactic cosmic rays.
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In the accompanying paper by Weil et al. (1996) we show that staurosporine (STS), in the presence of cycloheximide (CHX) to inhibit protein synthesis, induces apoptotic cell death in a large variety of nucleated mammalian cell types, suggesting that all nucleated mammalian cells constitutively express all of the proteins required to undergo programmed cell death (PCD). The reliability of that conclusion depends on the evidence that STS-induced, and (STS + CHS)-induced, cell deaths are bona fide examples of PCD. There is rapidly accumulating evidence that some members of the Ced-3/Interleukin-1 beta converting enzyme (ICE) family of cysteine proteases are part of the basic machinery of PCD. Here we show that Z-Val-Ala-Asp-fluoromethylketone (zVAD-fmk), a cell-permeable, irreversible, tripeptide inhibitor of some of these proteases, suppresses STS-induced and (STS + CHX)-induced cell death in a wide variety of mammalian cell types, including anucleate cytoplasts, providing strong evidence that these are all bona fide examples of PCD. We show that the Ced-3/ICE family member CPP32 becomes activated in STS-induced PCD, and that Bcl-2 inhibits this activation. Most important, we show that, in some cells at least, one or more CPP32-family members, but not ICE itself, is required for STS-induced PCD. Finally, we show that zVAD-fmk suppresses PCD in the interdigital webs in developing mouse paws and blocks the removal of web tissue during digit development, suggesting that this inhibition will be a useful tool for investigating the roles of PCD in various developmental processes.