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1.
Cell ; 177(4): 821-836.e16, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30982602

RESUMO

Whole-genome-sequencing (WGS) of human tumors has revealed distinct mutation patterns that hint at the causative origins of cancer. We examined mutational signatures in 324 WGS human-induced pluripotent stem cells exposed to 79 known or suspected environmental carcinogens. Forty-one yielded characteristic substitution mutational signatures. Some were similar to signatures found in human tumors. Additionally, six agents produced double-substitution signatures and eight produced indel signatures. Investigating mutation asymmetries across genome topography revealed fully functional mismatch and transcription-coupled repair pathways. DNA damage induced by environmental mutagens can be resolved by disparate repair and/or replicative pathways, resulting in an assortment of signature outcomes even for a single agent. This compendium of experimentally induced mutational signatures permits further exploration of roles of environmental agents in cancer etiology and underscores how human stem cell DNA is directly vulnerable to environmental agents. VIDEO ABSTRACT.


Assuntos
Carcinógenos Ambientais/classificação , Neoplasias/genética , Carcinógenos Ambientais/efeitos adversos , Dano ao DNA/genética , Análise Mutacional de DNA/métodos , Reparo do DNA/genética , Replicação do DNA , Perfil Genético , Genoma Humano/genética , Humanos , Mutação INDEL/genética , Mutagênese , Mutação/genética , Células-Tronco Pluripotentes/metabolismo , Sequenciamento Completo do Genoma/métodos
2.
Clin Exp Dermatol ; 46(3): 462-472, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33207021

RESUMO

The current COVID-19 pandemic is caused by the SARS-CoV-2 coronavirus. The initial recognized symptoms were respiratory, sometimes culminating in severe respiratory distress requiring ventilation, and causing death in a percentage of those infected. As time has passed, other symptoms have been recognized. The initial reports of cutaneous manifestations were from Italian dermatologists, probably because Italy was the first European country to be heavily affected by the pandemic. The overall clinical presentation, course and outcome of SARS-CoV-2 infection in children differ from those in adults as do the cutaneous manifestations of childhood. In this review, we summarize the current knowledge on the cutaneous manifestations of COVID-19 in children after thorough and critical review of articles published in the literature and from the personal experience of a large panel of paediatric dermatologists in Europe. In Part 1, we discuss one of the first and most widespread cutaneous manifestations of COVID-19, chilblain-like lesions, and in Part 2 we expanded to other manifestations, including erythema multiforme, urticaria and Kawasaki disease-like inflammatory multisystemic syndrome. In this part of the review, we discuss the histological findings of COVID-19 manifestations, and the testing and management of infected children for both COVID-19 and any other pre-existing conditions.


Assuntos
COVID-19/complicações , Dermatopatias Virais/patologia , Adolescente , Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19/diagnóstico , COVID-19/patologia , Teste para COVID-19 , Criança , Fármacos Dermatológicos/uso terapêutico , Exantema/tratamento farmacológico , Exantema/patologia , Exantema/virologia , Humanos , Síndrome de Nicolau/tratamento farmacológico , Síndrome de Nicolau/patologia , Síndrome de Nicolau/virologia , Pitiríase Rósea/patologia , Pitiríase Rósea/virologia , Púrpura/tratamento farmacológico , Púrpura/patologia , Púrpura/virologia , SARS-CoV-2 , Dermatopatias Virais/tratamento farmacológico , Urticária/tratamento farmacológico , Urticária/patologia , Urticária/virologia
3.
Clin Exp Dermatol ; 46(3): 451-461, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33166429

RESUMO

The current COVID-19 pandemic is caused by the SARS-CoV-2 coronavirus. The initial recognized symptoms were respiratory, sometimes culminating in severe respiratory distress requiring ventilation, and causing death in a percentage of those infected. As time has passed, other symptoms have been recognized. The initial reports of cutaneous manifestations were from Italian dermatologists, probably because Italy was the first European country to be heavily affected by the pandemic. The overall clinical presentation, course and outcome of SARS-CoV-2 infection in children differ from those in adults, as do the cutaneous manifestations of childhood. In this review, we summarize the current knowledge on the cutaneous manifestations of COVID-19 in children after thorough and critical review of articles published in the literature and from the personal experience of a large panel of paediatric dermatologists in Europe. In Part 1, we discussed one of the first and most widespread cutaneous manifestations of COVID-19, chilblain-like lesions. In this part of the review, we describe other manifestations, including erythema multiforme, urticaria and Kawasaki disease-like inflammatory multisystemic syndrome. In Part 3, we discuss the histological findings of COVID-19 manifestations, and the testing and management of infected children for both COVID-19 and any other pre-existing conditions.


Assuntos
COVID-19/complicações , Eritema Multiforme/virologia , Síndrome de Linfonodos Mucocutâneos/virologia , Urticária/virologia , Adolescente , COVID-19/patologia , Criança , Eritema Multiforme/patologia , Exantema/patologia , Exantema/virologia , Humanos , SARS-CoV-2 , Urticária/patologia
4.
Clin Exp Dermatol ; 46(3): 444-450, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33180982

RESUMO

The current COVID-19 pandemic is caused by the SARS-CoV-2 coronavirus. The initial recognized symptoms were respiratory, sometimes culminating in severe respiratory distress requiring ventilation, and causing death in a percentage of those infected. As time has passed, other symptoms have been recognized. The initial reports of cutaneous manifestations were from Italian dermatologists, probably because Italy was the first European country to be heavily affected by the pandemic. The overall clinical presentation, course and outcome of SARS-CoV-2 infection in children differ from those in adults as do the cutaneous manifestations of childhood. In this review, we summarize the current knowledge on the cutaneous manifestations of COVID-19 in children after thorough and critical review of articles published in the literature and from the personal experience of a large panel of paediatric dermatologists in Europe. In Part 1, we discuss one of the first and most widespread cutaneous manifestation of COVID-19, chilblain-like lesions. In Part 2, we review other manifestations, including erythema multiforme, urticaria and Kawasaki disease-like inflammatory multisystemic syndrome, while in Part 3, we discuss the histological findings of COVID-19 manifestations, and the testing and management of infected children, for both COVID-19 and any other pre-existing conditions.


Assuntos
COVID-19/complicações , Pérnio/virologia , Adolescente , COVID-19/diagnóstico , COVID-19/patologia , COVID-19/terapia , Teste para COVID-19 , Pérnio/imunologia , Pérnio/patologia , Criança , Humanos , Interferon Tipo I/imunologia , Remissão Espontânea , Fatores de Risco , SARS-CoV-2 , Trombose/etiologia , Vasculite/etiologia
6.
Spinal Cord ; 54(1): 57-64, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26282492

RESUMO

STUDY DESIGN: Phase- I/II, prospective, randomized, single-blind, controlled pilot study. PRIMARY OBJECTIVE: To determine the safety and feasibility of autologous bone marrow transplantation in patients with acute spinal cord injury (SCI) via two routes of transplantation as compared with controls. SETTING: Indian Spinal Injuries Center, New Delhi. METHODS: Twenty-one subjects with acute, American Spinal Injury Association Impairment Scale (AIS) A (complete), traumatic SCI with neurological level T1-T12, were recruited and randomized into three groups of seven subjects each. Two groups underwent cell transplantation through the intrathecal or intralesional route, whereas the third served as control. Participants were assessed at baseline and followed up at 6 months and 12-months post enrollment. Safety and tolerability were evaluated by monitoring for any adverse events. Efficacy was assessed through neurological, functional and psychological evaluation, as well as through electrophysiological studies and urodynamics. RESULTS: Surgery was tolerated well by all participants. There were no significant adverse events attributable to the procedure. There was no significant improvement in the neurological, electrophysiological or urodynamic efficacy variables. A statistically significant improvement in functional scores as evaluated by the Spinal Cord Independence Measure and International Spinal Cord Injury Scale was observed in all groups. CONCLUSIONS: The procedure is safe and feasible in AIS A participants with thoracic-level injuries at 12-months follow-up. No efficacy could be demonstrated that could be attributed to the procedure.


Assuntos
Transplante de Medula Óssea/métodos , Traumatismos da Medula Espinal/cirurgia , Resultado do Tratamento , Doença Aguda , Adolescente , Adulto , Eletrofisiologia , Feminino , Seguimentos , Humanos , Índia , Masculino , Exame Neurológico , Projetos Piloto , Testes Psicológicos , Estudos Retrospectivos , Transplante Autólogo , Adulto Jovem
7.
Br J Dermatol ; 172(5): 1407-11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25308318

RESUMO

Autosomal recessive congenital ichthyosis (ARCI) is a genetically heterogeneous disorder for which subtyping through molecular analysis can help determine the eventual phenotype and prognosis. We used whole-exome sequencing to identify a new homozygous splice-site mutation in ST14 (IVS5+1G>A), encoding matriptase, in a 4-year-old girl with ARCI from a consanguineous Kuwaiti family. Clinically, she also had hypotrichosis, which supported a diagnosis of ARCI type 11. Only four previous examples of pathogenic mutations in ST14 have been reported, and our findings expand the genotype-phenotype correlation for this subtype of ARCI. Our patient was the second child born to these parents; the first (deceased) and third children had congenital brain and eye abnormalities, of uncertain aetiology and with no precise diagnosis. Further analysis of our patient's exome dataset revealed heterozygosity for a splice-site mutation in POMT1 (IVS4+1G>T), encoding the protein O-mannosyltransferase, a gene implicated in Walker-Warburg syndrome. DNA sequencing in the third child showed homozygosity for this mutation in POMT1. The first-cousin parents were both heterozygous for the splice-site mutations in ST14 and POMT1. In this family, whole-exome sequencing provided accurate subtyping of a form of ARCI in one child and provide an explanation for an undiagnosed developmental disorder in two other children, findings that improve the prospects for diagnostic accuracy and genetic counselling, and demonstrate the impact of next-generation sequencing technologies on clinical genetics.


Assuntos
Transtornos Cromossômicos/diagnóstico , Ictiose/diagnóstico , Manosiltransferases/genética , Mutação/genética , Serina Endopeptidases/genética , Pré-Escolar , Transtornos Cromossômicos/genética , Consanguinidade , Exoma , Feminino , Estudo de Associação Genômica Ampla/métodos , Heterozigoto , Homozigoto , Humanos , Ictiose/genética , Sítios de Splice de RNA/genética
8.
Br J Dermatol ; 172(2): 527-31, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25059916

RESUMO

Only two homozygous nonsense mutations in the epidermal isoform of the dystonin gene, DST-e, have been reported previously in autosomal recessive epidermolysis bullosa simplex (EBS); the affected pedigrees were Kuwaiti and Iranian. This subtype of EBS is therefore considered to be a rare clinicopathological entity. In this study, we identified four seemingly unrelated Kuwaiti families in which a total of seven individuals had predominantly acral trauma-induced blistering since infancy. All affected individuals were homozygous for the mutation p.Gln1124* in DST-e, the same mutation that was identified in the originally reported family from Kuwait. Haplotype analysis in the five pedigrees (including the previous case) revealed a shared block of ~60 kb of genomic DNA across the site of the mutation, consistent with a founder effect. Most heterozygotes had no clinical abnormalities although one subject had mild transient skin fragility during childhood, an observation noted in the previously reported Iranian pedigree, suggesting that the condition may also be semidominant in some pedigrees rather than purely autosomal recessive. Our study reveals propagation of a mutant ancestral allele in DST-e throughout Kuwait, indicating that this subtype of EBS may be more common in Kuwait, and perhaps other Middle Eastern countries, than is currently appreciated.


Assuntos
Proteínas de Transporte/genética , Códon sem Sentido/genética , Proteínas do Citoesqueleto/genética , Epidermólise Bolhosa Simples/genética , Dermatoses do Pé/genética , Dermatoses da Mão/genética , Proteínas do Tecido Nervoso/genética , Vesícula/genética , Consanguinidade , Distonina , Feminino , Efeito Fundador , Genótipo , Heterozigoto , Homozigoto , Humanos , Kuweit , Masculino , Linhagem , Fenótipo , Recidiva
11.
Spinal Cord ; 53(5): 353-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25224600

RESUMO

OBJECTIVE: This study aims to understand the demographics, mode of trauma, hospital stay, complications, neurological improvement, mortality and expenditure incurred by Indian patients with spinal trauma and ankylosing spondylitis (AS). METHODS: Retrospective analysis of the patient data admitted to a tertiary referral hospital from 2008 to 2013 with the diagnosis of AS and spinal trauma was carried out. The variables studied were demographics, mode of trauma, neurological status, neurological improvement, involved vertebral level, duration of hospital stay, comorbid factors, expenditure and complications during the stay. RESULTS: Forty-six patients with diagnosis of AS with spine trauma were admitted over the last 5 years with a total of 52 fractures. All were male patients; 58.6% had injury because of trivial trauma and 78.2% patients presented with neurological injury. C5 C6, C6 C7, C7 D1 and D12 were the most common injured level. Fractures through intervertebral disc were most common in cervical spine. Of the patients, 52.7% had shown neurological improvement of at least grade 1(AIS). Mean expenditure of patient admitted with spinal cord injury (SCI) with AS is 7957 USD (United States dollar), which is around five times the per capita income in India (as per year 2013). CONCLUSION: Males with AS are much more prone to spinal fractures than females and its incidence may be higher than previously reported. Domestic falls are the most common mechanism of spinal trauma in this population. High velocity injuries are associated with complete SCI. The study reinforces the need for development of subsidized spinal care services for SCI management.


Assuntos
Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/epidemiologia , Espondilite Anquilosante/complicações , Espondilite Anquilosante/epidemiologia , Adulto , Idoso , Comorbidade , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Traumatismos da Medula Espinal/economia , Traumatismos da Medula Espinal/mortalidade , Espondilite Anquilosante/economia , Espondilite Anquilosante/mortalidade
13.
Int J Cosmet Sci ; 36(3): 273-83, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24575878

RESUMO

BACKGROUND: A systematic and detailed study has been designed and conducted, taking into account some of the proposed benefits such as increased efficiency, transparency, unique texture, protection of active ingredient and higher consumer compliance of cosmetics containing nano-sized metal oxides. METHODS: This study also presents an in vitro method to determine sun protection factor of the investigational sunscreen cream samples containing zinc oxide and titanium dioxide with a varied range of particle size. Finally, a comparative study has been conducted between metal oxide particles, conventional as well as nanoparticles. RESULTS: All the skin cosmetics formulated were thermally stable with a pH ranging from 7.9 to 8.2. Moreover, the fatty acid substance content and residue were found to be analogous to the standard values in each skin cosmetic. The skin cosmetics containing the titanium or zinc oxide nanoparticles were found to have improved spreadability as compared to skin cosmetics containing conventional titanium or zinc oxide particles, respectively. All skin cosmetics were found to have uniform distribution of the particles. The sunscreen creams containing zinc oxide nanoparticles and titanium dioxide nanoparticles were found to have higher in vitro sun protection factor (SPF of 3.65 for ZnO nanoparticles and 4.93 for TiO2 nanoparticles) as compared to that of sunscreen creams containing conventional zinc oxide particles (SPF = 2.90) and conventional titanium dioxide (SPF = 1.29), clearly indicating the effect of reduction in particles size, from micro to nano, on the sun protection factor. CONCLUSION: Good texture, better spreadability and enhanced in vitro SPF proved the advantageous role of nanoparticles in cosmetics.


Assuntos
Nanopartículas/química , Pele/efeitos dos fármacos , Fator de Proteção Solar/normas , Protetores Solares/química , Titânio/química , Óxido de Zinco/química , Animais , Humanos , Técnicas In Vitro/métodos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos , Ratos Wistar , Viscosidade
15.
Sci Rep ; 13(1): 5444, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37012265

RESUMO

Crop improvement is a key innovation area in the pursuit of sustainable food systems. However, realising its potential requires integration of the needs and priorities of all agri-food chain stakeholders. In this study, we provide a multi-stakeholder perspective on the role of crop improvement in future-proofing the European food system. We engaged agri-business, farm- and consumer-level stakeholders, and plant scientists through an online survey and focus groups. Four of each group's top five priorities were shared and related to environmental sustainability goals (water, nitrogen and phosphorus efficiency, and heat stress). Consensus was identified on issues including considering existing alternatives to plant breeding (e.g. management strategies), minimising trade-offs, and addressing geographical variation in needs. We conducted a rapid evidence synthesis on the impacts of priority crop improvement options, highlighting the urgent need for further research examining downstream sustainability impacts to identify concrete targets for plant breeding innovation as a food systems solution.


Assuntos
Melhoramento Vegetal , Grupos Focais , Fazendas
17.
Clin Exp Dermatol ; 37(5): 509-11, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22712859

RESUMO

Congenital leukaemia (CL) is a rare malignancy that accounts for < 1% of cases of childhood leukaemias. Leukaemia cutis (LC) refers to cutaneous infiltration with leukaemic cells, and is seen in 30-50% of CL cases. It may precede, follow or occur simultaneously with leukaemia. If left untreated, the prognosis is usually poor, but early diagnosis and treatment may result in a favourable prognosis. We report a case of congenital leukaemia cutis with a progressive, violaceous papulonodular eruption (a 'blueberry muffin' rash), which had been noted at birth, as a presenting sign of acute myeloid leukaemia (AML), which on investigation was classified as AML, FAB M2 type with a t(8; 21)(p11;q22) chromosomal defect. The patient had a favourable response to AML chemotherapy.


Assuntos
Leucemia Mieloide Aguda/congênito , Neoplasias Cutâneas/congênito , Feminino , Humanos , Recém-Nascido , Leucemia Mieloide Aguda/patologia , Neoplasias Cutâneas/patologia
18.
PLoS Genet ; 5(9): e1000649, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19763161

RESUMO

A follow-up study of a large Utah family with significant linkage to chromosome 2q24 led us to identify a new febrile seizure (FS) gene, SCN9A encoding Na(v)1.7. In 21 affected members, we uncovered a potential mutation in a highly conserved amino acid, p.N641Y, in the large cytoplasmic loop between transmembrane domains I and II that was absent from 586 ethnically matched population control chromosomes. To establish a functional role for this mutation in seizure susceptibility, we introduced the orthologous mutation into the murine Scn9a ortholog using targeted homologous recombination. Compared to wild-type mice, homozygous Scn9a(N641Y/N641Y) knockin mice exhibit significantly reduced thresholds to electrically induced clonic and tonic-clonic seizures, and increased corneal kindling acquisition rates. Together, these data strongly support the SCN9A p.N641Y mutation as disease-causing in this family. To confirm the role of SCN9A in FS, we analyzed a collection of 92 unrelated FS patients and identified additional highly conserved Na(v)1.7 missense variants in 5% of the patients. After one of these children with FS later developed Dravet syndrome (severe myoclonic epilepsy of infancy), we sequenced the SCN1A gene, a gene known to be associated with Dravet syndrome, and identified a heterozygous frameshift mutation. Subsequent analysis of 109 Dravet syndrome patients yielded nine Na(v)1.7 missense variants (8% of the patients), all in highly conserved amino acids. Six of these Dravet syndrome patients with SCN9A missense variants also harbored either missense or splice site SCN1A mutations and three had no SCN1A mutations. This study provides evidence for a role of SCN9A in human epilepsies, both as a cause of FS and as a partner with SCN1A mutations.


Assuntos
Anormalidades Múltiplas/genética , Epilepsia/complicações , Epilepsia/genética , Convulsões Febris/etiologia , Convulsões Febris/genética , Canais de Sódio/genética , Anormalidades Múltiplas/fisiopatologia , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Animais , Sequência de Bases , Análise Mutacional de DNA , Eletrochoque , Epilepsia/fisiopatologia , Feminino , Técnicas de Introdução de Genes , Humanos , Excitação Neurológica/fisiologia , Masculino , Camundongos , Dados de Sequência Molecular , Mutação/genética , Canal de Sódio Disparado por Voltagem NAV1.1 , Canal de Sódio Disparado por Voltagem NAV1.7 , Proteínas do Tecido Nervoso/genética , Linhagem , Subunidades Proteicas/genética , Convulsões Febris/fisiopatologia , Alinhamento de Sequência , Canais de Sódio/química , Síndrome
19.
Pharmazie ; 67(2): 147-55, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22512085

RESUMO

Hydroxypropyl methylcellulose (HPMC) is now available in modified hydrophobic forms (Sangelose). In this paper, the effect of viscosity grade and HPMC concentration on in vitro release kinetics of a topically applied drug were studied using gel formulations of a nonsteroidal anti-inflammatory drug (NSAID), diclofenac potassium (DP), with different viscosity grades of the polymer (60L, 60 M, 90 M for hydrophobic HPMC and 50 cPs for conventional hydrophilic HPMC) in different proportions. It was found that hydrophobic HPMC-based gels having a higher viscosity and lower polymer concentration release a notably higher amount of drug compared with hydrophilic HPMC-based gels containing a higher concentration of polymer but with lower viscosity. For gels, the suitability of different common empirical (zero-order, first-order, and Higuchi), and semi-empirical (Ritger-Peppas and Peppas-Sahlin) models, and some new statistical (logistic, log-logistic, Weibull, Gumbel, and generalized extreme value distribution) models to describe the drug release profile were tested through non-linear least-square curve fitting. A general purpose mathematical analysis tool MATLAB was used. Further, instead of the widely used transformed linear fit method, direct fitting was used in the paper to avoid any form of truncation and transformation errors. The results revealed that the log-logistic distribution, amongst all the models investigated, was the best fit for hydrophobic formulations. For hydrophilic ones, the semi-empirical models and Weibull distribution worked best, although log-logistic also showed a close fit. The shape parameter for the log-logistic and Weibull distribution conveys vital information about the rate of release and helps improve understanding of drug release profiles.


Assuntos
Metilcelulose/análogos & derivados , Algoritmos , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Simulação por Computador , Preparações de Ação Retardada , Diclofenaco/administração & dosagem , Diclofenaco/química , Géis , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Derivados da Hipromelose , Cinética , Modelos Logísticos , Metilcelulose/química , Modelos Estatísticos , Dinâmica não Linear , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Software , Solubilidade , Viscosidade
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