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1.
Soc Sci Med ; 315: 115493, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36423539

RESUMO

The C-reactive protein point-of-care test (CRP-POCT) can help distinguish between viral and bacterial infection and has been promoted as a strategy to improve antimicrobial stewardship. The test is widely used in Sweden. National guidelines advocate conservative use in primary care consultations with patients presenting with symptoms of respiratory tract infection (RTI). Previous research suggests low adherence to guidelines. We provide new insights into the communication surrounding the CRP-POCT by documenting how the decision to administer the test is interactionally motivated and organized in Swedish primary care. The data consists of video-recordings of RTI-consultations. A CRP-POCT was performed in nearly two thirds of the consultations and our study is focused on a subset where the test is ordered by a medical doctor. We find that doctors order the test during the transition from or after physical examination, a practice that aligns with national guidelines. Guidelines indicate that pathological findings from physical examination are warrants for ordering the test but we only found one example where this was communicated to the patient. A more prevalent pattern was that doctors ordered the CRP-POCT even though the outcome of the physical examination was assessed as normal. Our analyses of these show that doctors can provide the rationale for ordering the test in subtle ways and that failure to provide a rationale is treated as a noticeable absence. We also find that the CRP-POCT can be used to reconcile the contrast between the normal physical examination and the patient's problem presentation. Doctors can also order the test in ways that position the CRP-POCT as criterial for antibiotic prescription. Consultations where the patients described the symptoms as particularly severe and/or persistent were more likely to engender elaborate accounts than consultations where patients presented their symptoms as less problematic.


Assuntos
Proteína C-Reativa , Infecções Respiratórias , Humanos , Testes Imediatos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Encaminhamento e Consulta , Comunicação , Atenção Primária à Saúde
2.
Hum Mol Genet ; 28(16): 2675-2685, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31216356

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disease worldwide. Familial cases suggest genetic components; however, monogenetic causes are few, and the vast majority of incidences have unknown cause. Sequencing efforts have focused on germline mutations, but improved technology has opened up for studies on somatic mutations in affected brain tissue samples. Here we use ultra-deep sequencing on brain and blood from early-onset AD (EOAD) and late-onset AD (LOAD) patients and non-AD individuals (n = 16). In total, 2.86 Mb of genomic regions, previously associated with AD, were targeted included 28 genes and upstream and downstream regulatory regions. Tailored downstream bioinformatics filtering identified 11 somatic single nucleotide variants in the temporal cortex in AD patients and none in the controls. One variant was validated to be present at 0.4% allele frequency in temporal cortex of a LOAD patient. This variant was predicted to affect transcription factor binding sites upstream of the CD55 gene, contributing to AD pathogenesis by affecting the complement system. Our results suggest that future studies targeting larger portions of the genome for somatic mutation analysis are important to obtain an increased understanding for the molecular basis of both EOAD and LOAD.


Assuntos
Regiões 5' não Traduzidas , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Antígenos CD55/genética , Antígenos CD55/metabolismo , Mutação , Lobo Temporal/metabolismo , Fatores de Transcrição/metabolismo , Idade de Início , Idoso , Alelos , Desequilíbrio Alélico , Doença de Alzheimer/patologia , Sítios de Ligação , Estudos de Casos e Controles , Análise Mutacional de DNA , Bases de Dados Genéticas , Suscetibilidade a Doenças , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Reprodutibilidade dos Testes
3.
Neurobiol Aging ; 84: 241.e21-241.e25, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30992141

RESUMO

Frontotemporal dementia (FTD) is the second most common early-onset dementia. Up to half of the cases are familial, and several mutations have been identified as pathogenic. Repeat expansion mutations in C9orf72 are the most common genetic cause of FTD and are particularly frequent in Sweden and Finland. We aimed to determine the mutation frequency in patients with FTD ascertained at a memory clinic in Sweden and assess the inheritance pattern in the families. We screened 132 patients with FTD for mutations in C9orf72, GRN, and MAPT, and the frequency was 34.1%. Two novel variations, not previously published, were found; a pathogenic GRN mutation and a MAPT variation in intron 9 that we report as VUS. The likelihood of finding a mutation was highest in patients with a clear family history of dementia or motor neuron disease (76%), but mutations were also found in apparent sporadic cases. This confirms that FTD cohorts from Sweden have a relatively higher risk of an underlying mutation in all risk categories compared with other reported cohorts.


Assuntos
Proteína C9orf72/genética , Demência Frontotemporal/genética , Mutação , Humanos , Porfiria Aguda Intermitente
4.
Acta Neuropathol Commun ; 5(1): 43, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28595629

RESUMO

Alzheimer disease (AD) is a progressive neurodegenerative disorder and the most common form of dementia. The majority of AD cases are sporadic, while up to 5% are families with an early onset AD (EOAD). Mutations in one of the three genes: amyloid beta precursor protein (APP), presenilin 1 (PSEN1) or presenilin 2 (PSEN2) can be disease causing. However, most EOAD families do not carry mutations in any of these three genes, and candidate genes, such as the sortilin-related receptor 1 (SORL1), have been suggested to be potentially causative. To identify AD causative variants, we performed whole-exome sequencing on five individuals from a family with EOAD and a missense variant, p.Arg1303Cys (c.3907C > T) was identified in SORL1 which segregated with disease and was further characterized with immunohistochemistry on two post mortem autopsy cases from the same family. In a targeted re-sequencing effort on independent index patients from 35 EOAD-families, a second SORL1 variant, c.3050-2A > G, was found which segregated with the disease in 3 affected and was absent in one unaffected family member. The c.3050-2A > G variant is located two nucleotides upstream of exon 22 and was shown to cause exon 22 skipping, resulting in a deletion of amino acids Gly1017- Glu1074 of SORL1. Furthermore, a third SORL1 variant, c.5195G > C, recently identified in a Swedish case control cohort included in the European Early-Onset Dementia (EU EOD) consortium study, was detected in two affected siblings in a third family with familial EOAD. The finding of three SORL1-variants that segregate with disease in three separate families with EOAD supports the involvement of SORL1 in AD pathology. The cause of these rare monogenic forms of EOAD has proven difficult to find and the use of exome and genome sequencing may be a successful route to target them.


Assuntos
Doença de Alzheimer/genética , Predisposição Genética para Doença , Variação Genética , Proteínas Relacionadas a Receptor de LDL/genética , Proteínas de Membrana Transportadoras/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Estudos de Coortes , Família , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Sequenciamento do Exoma
5.
J Hum Genet ; 62(2): 321-324, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27557666

RESUMO

Hexanucleotide expansion mutations in the chromosome 9 open reading frame 72 (C9orf72) gene is the most common genetic cause for frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). SNP haplotype analyses have suggested that all C9orf72 expansion mutations originate from a common founder. However, not all C9orf72 expansion mutation carriers have the same haplotype. To investigate if the C9orf72 expansion mutation carriers in Sweden share a common founder, we have genotyped SNPs flanking the C9orf72 expansion mutation in cases with FTD, FTD-ALS or ALS to perform haplotype analysis. We have genotyped 57 SNPs in 232 cases of which 45 carried the C9orf72 expansion mutation. Two risk haplotypes consisting of 31 SNPs, spanning 131 kbp, were found to be significantly associated with the mutation. In summary, haplotype analysis on Swedish C9orf72 expansion mutation carriers indicates that the C9orf72 expansion mutation arose on at least two risk haplotypes.


Assuntos
Expansão das Repetições de DNA/genética , Haplótipos/genética , Proteínas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/genética , Proteína C9orf72 , Feminino , Demência Frontotemporal/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Suécia
6.
Eur J Hum Genet ; 25(1): 85-93, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-27782108

RESUMO

A remarkable proportion of factors causing genetic predisposition to breast cancer (BC) are unknown in non-BRCA1/2 families. Exome sequencing was performed for 13 high-risk Finnish hereditary breast and/or ovarian cancer (HBOC) families to detect variants contributing to BC susceptibility. After filtering, 18 candidate variants in DNA damage response (DDR) pathway genes were screened in 129 female HBOC patients, up to 989 female controls, and 31 breast tumours by Sanger sequencing/TaqMan assays. In addition, two variants were further studied in 49 male BC patients and 909 male controls. Second, all variants predicted to affect function in six early-onset BC patients were analysed in detail. Variants in ATM, MYC, PLAU, RAD1, and RRM2B were enriched in female HBOC patients compared with controls (odds ratio 1.16-2.16). A rare nonsynonymous variant in RAD50 was detected in a male BC patient. In addition, a very rare BRCA1 variant was identified in a single high-risk family. None of the variants showed wild-type allele loss in breast tumours. Furthermore, novel variants predicted to affect function were detected in early-onset patients in genes, which target DNA repair and replication, signalling, apoptosis, and cell cycle pathways. Family-specific enrichment of multiple DDR pathway gene defects likely explains BC predisposition in the studied families. These findings provide new information on potential BC-related pathways and an excellent premise for future studies.


Assuntos
Neoplasias da Mama/genética , Exoma/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Proteínas de Ciclo Celular/genética , Reparo do DNA/genética , Exonucleases/genética , Feminino , Finlândia , Genótipo , Mutação em Linhagem Germinativa/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Linhagem , Proteínas Proto-Oncogênicas c-myc/genética , Ribonucleotídeo Redutases/genética
7.
J Neuropathol Exp Neurol ; 74(11): 1061-70, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26469248

RESUMO

We examined the extent to which tauopathy distribution, as determined by Braak staging, might be predicted by various risk factors in older individuals. The Swedish Twin Registry provided extensive information on neuropsychological function, lifestyle, and cardiovascular risk factors of 128 patients for whom autopsy data including Braak staging were available. Logistic regression was used to develop a prognostic model that targeted discrimination between Braak stages 0 to II and III to VI. The analysis showed that Braak stages III to VI were significantly predicted by having 1 or more APOE ε4 alleles, older age, high total cholesterol, absence of diabetes and cardiovascular disease, and poorer scores on the Wechsler Adult Intelligence Score Information test, verbal fluency, and recognition memory but better verbal recall. The algorithm predicted Braak stages III to VI well (receiver-operating characteristic area under curve, 0.897; 95% confidence interval, 0.842-0.951). Using a cutoff of 50% risk or more, the sensitivity was 85%, the specificity was 70%, and the negative predictive value was 69%. This study demonstrates that tauopathy distribution can be accurately predicted using a combination of antemortem patient data. These results provide further insight into tauopathy development and AD-related disease mechanisms and suggest a prognostic model that predicts the spread of neurofibrillary tangles above the transentorhinal stage.


Assuntos
Encéfalo/patologia , Diagnóstico , Emaranhados Neurofibrilares/patologia , Tauopatias/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Humanos , Modelos Logísticos , Masculino , Valor Preditivo dos Testes , Curva ROC , Sistema de Registros , Fatores de Risco , Índice de Gravidade de Doença , Suécia , Tauopatias/genética
8.
Arch Toxicol ; 89(3): 423-36, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24798087

RESUMO

The environmental neurotoxin ß-N-methylamino-L-alanine (BMAA) has been implicated in the etiology of neurodegenerative disease, and recent studies indicate that BMAA can be misincorporated into proteins. BMAA is a developmental neurotoxicant that can induce long-term learning and memory deficits, as well as regionally restricted neuronal degeneration and mineralization in the hippocampal CA1. The aim of the study was to characterize long-term changes (2 weeks to 6 months) further in the brain of adult rats treated neonatally (postnatal days 9-10) with BMAA (460 mg/kg) using immunohistochemistry (IHC), transmission electron microscopy, and laser capture microdissection followed by LC-MS/MS for proteomic analysis. The histological examination demonstrated progressive neurodegenerative changes, astrogliosis, microglial activation, and calcification in the hippocampal CA1 3-6 months after exposure. The IHC showed an increased staining for α-synuclein and ubiquitin in the area. The ultrastructural examination revealed intracellular deposition of abundant bundles of closely packed parallel fibrils in neurons, axons, and astrocytes of the CA1. Proteomic analysis of the affected site demonstrated an enrichment of chaperones (e.g., clusterin, GRP-78), cytoskeletal and intermediate filament proteins, and proteins involved in the antioxidant defense system. Several of the most enriched proteins (plectin, glial fibrillar acidic protein, vimentin, Hsp 27, and ubiquitin) are known to form complex astrocytic inclusions, so-called Rosenthal fibers, in the neurodegenerative disorder Alexander disease. In addition, TDP-43 and the negative regulator of autophagy, GLIPR-2, were exclusively detected. The present study demonstrates that neonatal exposure to BMAA may offer a novel model for the study of hippocampal fibril formation in vivo.


Assuntos
Diamino Aminoácidos/toxicidade , Região CA1 Hipocampal/efeitos dos fármacos , Calcinose/metabolismo , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/efeitos dos fármacos , Chaperonas Moleculares/metabolismo , Animais , Animais Recém-Nascidos , Região CA1 Hipocampal/crescimento & desenvolvimento , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/ultraestrutura , Calcinose/induzido quimicamente , Cromatografia Líquida , Toxinas de Cianobactérias , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Imuno-Histoquímica , Microscopia Eletrônica de Transmissão , Dobramento de Proteína , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Ubiquitina/metabolismo , alfa-Sinucleína/metabolismo
9.
Toxicol Sci ; 130(2): 391-404, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22872059

RESUMO

The cyanobacterial toxin ß-N-methylamino-L-alanine (BMAA) has been proposed to contribute to neurodegenerative disease. We have previously reported a selective uptake of BMAA in the mouse neonatal hippocampus and that exposure during the neonatal period causes learning and memory impairments in adult rats. The aim of this study was to characterize effects in the brain of 6-month-old rats treated neonatally (postnatal days 9-10) with the glutamatergic BMAA. Protein changes were examined using the novel technique Matrix-Assisted Laser Desorption Ionization (MALDI) imaging mass spectrometry (IMS) for direct imaging of proteins in brain cryosections, and histological changes were examined using immunohistochemistry and histopathology. The results showed long-term changes including a decreased expression of proteins involved in energy metabolism and intracellular signaling in the adult hippocampus at a dose (150 mg/kg) that gave no histopathological lesions in this brain region. Developmental exposure to a higher dose (460 mg/kg) also induced changes in the expression of S100ß, histones, calcium- and calmodulin-binding proteins, and guanine nucleotide-binding proteins. At this dose, severe lesions in the adult hippocampus including neuronal degeneration, cell loss, calcium deposits, and astrogliosis were evident. The data demonstrate subtle, sometimes dose-dependent, but permanent effects of a lower neonatal dose of BMAA in the adult hippocampus suggesting that BMAA could potentially disturb many processes during the development. The detection of BMAA in seafood stresses the importance of evaluating the magnitude of human exposure to this neurotoxin.


Assuntos
Diamino Aminoácidos/toxicidade , Toxinas Bacterianas/toxicidade , Hipocampo/efeitos dos fármacos , Toxinas Marinhas/toxicidade , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/induzido quimicamente , Síndromes Neurotóxicas/etiologia , Fatores Etários , Animais , Animais Recém-Nascidos , Toxinas de Cianobactérias , Relação Dose-Resposta a Droga , Metabolismo Energético/efeitos dos fármacos , Contaminação de Alimentos , Hipocampo/metabolismo , Hipocampo/patologia , Imuno-Histoquímica , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Ratos , Ratos Wistar , Medição de Risco , Transdução de Sinais/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fatores de Tempo
10.
Prosthet Orthot Int ; 35(1): 20-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21515886

RESUMO

BACKGROUND: The 'Convention on the Rights of Persons with Disabilities' (CRPD) requires governments to meet the assistive technology needs of citizens. However, the access to assistive technology in developing countries is severely limited, which is aggravated by a lack of related services. OBJECTIVES: To summarize current knowledge on assistive technology for low- and lower-middle-income countries published in 1995 or later, and to provide recommendations that facilitate implementation of the CRPD. STUDY DESIGN: Literature review. METHODS: Literature was searched in web-based databases and reference lists. Studies carried out in low- and lower-middle-income countries, or addressing assistive technology for such countries, were included. RESULTS: The 52 included articles are dominated by product oriented research on leg prostheses and manual wheelchairs. Less has been published on hearing aids and virtually nothing on the broad range of other types of assistive technology. CONCLUSIONS: To support effective implementation of the CRPD in these countries, there is a need for actions and research related particularly to policies, service delivery, outcomes and international cooperation, but also to product development and production. CLINICAL RELEVANCE: The article has a potential to contribute to CRPD compliant developments in the provision of assistive technology in developing countries by providing practitioners with an overview of published knowledge and researchers with identified research needs.


Assuntos
Países em Desenvolvimento , Pessoas com Deficiência , Direitos do Paciente/tendências , Tecnologia Assistiva/tendências , Humanos
12.
Int J Mol Med ; 23(5): 621-31, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19360321

RESUMO

Serum alanine aminotransferase (ALT) is used as a clinical marker of hepatotoxicity. Three forms of human ALT have been identified, ALT1 and 2 and an alternative splice variant of ALT2 (herein called ALT2_2). The standard ALT activity assay does not discriminate between ALT from different organs, or the isoforms measured in the plasma. Here, we show that ALT1 and 2 possess similar enzymatic activity for alanine and pyruvate but with different Km and kcat values, while recombinant ALT2_2 protein does not possess any enzymatic activity. Isolation of organelles from cultured human skeletal muscle cells, showed localisation of ALT2 to the mitochondrial fraction and endoplasmatic reticulum (ER), but not to the cytosol. In human hepatocytes, on the other hand, ALT1 was only localised to the cytosol and ER, with no detection in mitochondria. ALT2 was not detected in cultured human hepatocytes, liver extract or tissue using Western blotting or immunohistochemistry. The islet of Langerhans and cardiomyocytes were other examples of cells with high expression of catalytic ALT2. A clinical method for selective measurement of ALT1 and 2 in human plasma is described, and both ALT1 and 2 were immunoprecipitated from human plasma and structurally detected using Western blotting techniques.


Assuntos
Alanina Transaminase/análise , Alanina Transaminase/sangue , Fígado/metabolismo , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/metabolismo , Células Cultivadas , Feminino , Hepatócitos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Plasma/química , Plasma/metabolismo , Proteínas Recombinantes/metabolismo , Soro/metabolismo , Especificidade por Substrato , Adulto Jovem
13.
Expert Rev Gastroenterol Hepatol ; 2(3): 337-55, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19072384

RESUMO

Chronic inflammatory bowel diseases (IBD), such as Crohn's disease and ulcerative colitis, are recurrent and aggressive inflammatory disorders that are most likely the result of an overly aggressive immune response to ubiquitous intestinal antigens in a genetically susceptible host. Despite decades of intense research, our knowledge of factors causing IBD remains incomplete and, therefore, conventional therapy to induce and maintain remission works in a symptomatic fashion, merely suppressing the immune response. Probiotic bacteria have long been known to confer health benefits, especially with regard to intestinal disorders. Although there is mounting evidence from in vitro and animal experiments supporting the use of probiotics in IBD, clinical trials have not provided definite evidence for the therapeutic effect of probiotic therapy in IBD to date. This is with the notable exception of pouchitis and the maintenance of remission in ulcerative colitis, whereas Crohn's disease and active ulcerative colitis do not seem amenable to probiotic intervention. The next 5 years will see more trials targeting specific clinical settings using tailor-made probiotic combinations, taking into account our increasing knowledge of individual probiotic properties and the diversity of these microorganisms.


Assuntos
Sistema Digestório/microbiologia , Doenças Inflamatórias Intestinais/terapia , Probióticos/uso terapêutico , Humanos
14.
Toxicol Pathol ; 36(5): 727-37, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18648100

RESUMO

Dogs treated with AR-H047108, an imidazopyridine potassium competitive acid blocker (P-CAB), developed clinical signs of hepatic dysfunction as well as morphologically manifest hepatotoxicity in repeat-dose toxicity studies. An investigative one-month study was performed, with interim euthanasia after one and two weeks. A detailed histopathological and immunohistochemical characterization of the liver lesions was conducted, including markers for fibrosis, Kupffer cell activation, apoptosis, and endothelial injury. In addition, hepatic retinoid and procollagen 1alpha2 mRNA levels in livers of dogs treated with AR-H047108 were analyzed. The results showed an early inflammatory process in central veins and centrilobular areas, present after one week of treatment. This inflammatory reaction was paralleled by activation of stellate/Ito cells to myofibroblasts and was associated with sinusoidal and centrivenular fibrosis. The early activation of stellate cells coincided with a significant decrease in retinyl ester levels, and a significant increase in procollagen 1alpha2 mRNA levels, in the liver. At later time points (three and six months), there was marked sinusoidal fibrosis in centrilobular areas, as well as occlusion of central veins resulting from a combination of fibrosis and increased thickness of smooth muscle bundles in the vessel wall. The pattern of lesions suggests a veno-occlusive-disease (VOD)-like scenario, possibly linked to the imidazopyridine chemical structure of the compound facilitated by specific morphological features of the dog liver.


Assuntos
Hepatopatia Veno-Oclusiva/patologia , Hepatócitos/patologia , Imidazóis/toxicidade , Fígado/patologia , Inibidores da Bomba de Prótons/toxicidade , Piridinas/toxicidade , Animais , Cães , Relação Dose-Resposta a Droga , Feminino , Fibrose/induzido quimicamente , Fibrose/patologia , Hepatopatia Veno-Oclusiva/induzido quimicamente , Hepatopatia Veno-Oclusiva/metabolismo , Hepatócitos/metabolismo , Imidazóis/química , Imuno-Histoquímica , Células de Kupffer/metabolismo , Células de Kupffer/patologia , Fígado/metabolismo , Masculino , Estrutura Molecular , Inibidores da Bomba de Prótons/química , Piridinas/química , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica
15.
Biol Lett ; 3(3): 314-7, 2007 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-17412671

RESUMO

Predation is arguably one of the main driving forces of early metazoan evolution, yet the fossil record of predation during the Ediacaran-Early Cambrian transition is relatively poor. Here, we present direct evidence of failed durophagous (shell-breaking) predation and subsequent shell repair in the Early Cambrian (Botoman) epibenthic mollusc Marocella from the Mernmerna Formation and Oraparinna Shale in the Flinders Ranges, South Australia. This record pushes back the first appearance of durophagy on molluscs by approximately 40Myr.


Assuntos
Estruturas Animais/patologia , Fósseis , Moluscos/anatomia & histologia , Comportamento Predatório/fisiologia , Animais , Moluscos/fisiologia
16.
Antivir Ther ; 11(8): 1031-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17302373

RESUMO

OBJECTIVE: To investigate the prevalence of HIV-1 with major drug resistance-associated mutations among 261 men who have sex with men (MSM) who were newly diagnosed as HIV-1-infected at Venhälsan, Stockholm, between 1992-2002. METHODS: Major resistance-associated mutations were identified using an in-house method on stored plasma samples collected within 6 months of diagnosis. Additional samples were investigated from selected patients. Phylogenetic tree analyses were used to study evolutionary relationships between the viruses. Epidemiological data were retrieved from the partner notification investigations and the medical records. RESULTS: Informed consent as well as results from the resistance test were available for 201 out of 261 patients (77%) diagnosed during 1992-2002. Viruses from 28 of these 201 patients (14%) displayed major resistance-associated mutations; 27 of these viruses displayed only zidovudine/stavudine resistance-associated mutations. None of the patients displayed resistance mutations to protease inhibitors. The prevalence of resistance-associated mutations decreased over time; 20% in 1992-1996 versus 9% in 1997-2002 (P=0.04). A transmission cluster involving six patients with a singleton M41L mutation was identified. These viruses were phenotypically sensitive to zidovudine and stavudine. The M41L mutation, as well as most other resistance mutations, was stable for many years after transmission and may have been fixated by other putative compensatory mutations. CONCLUSIONS: In this Swedish population of MSM with newly diagnosed HIV-1 infection, the prevalence of resistance-associated mutations decreased over time. Reversion of resistance-associated mutations following transmission was slow and incomplete. A large transmission cluster with an interesting M41L singleton mutation was also observed.


Assuntos
Farmacorresistência Viral Múltipla , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/genética , Homossexualidade Masculina , Mutação/genética , Adulto , Idoso , Fármacos Anti-HIV/farmacologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Suécia/epidemiologia
17.
AIDS Res Hum Retroviruses ; 21(3): 221-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15795528

RESUMO

The objective of this study was to investigate the short-term virological outcome of antiretroviral combination therapy (ART) in relation to infection with different HIV-1 genetic subtypes. Antiretroviral drug-naive patients in Sweden were prospectively enrolled and followed for 6 months when starting ART in the period from January 1998 to January 2002. Plasma-HIV-1 RNA levels, CD4 counts, and type of ART regimen were recorded. The HIV-1 subtype was determined by direct sequencing of regions of the env or pol genes. Data from 172 patients who harbored subtypes A, B, C, D, G, and CRF01_AE were analyzed (32 A, 44 B, 34 C, 18 D, 5 G, and 19 CRF01_AE). Of all patients 84% had undetectable plasma HIV-1 RNA levels after 6 months of ART. Patients infected with CRF01_AE more often had undetectable HIV-1 RNA plasma levels than patients infected with subtypes A or D. However, the possibility that this difference is due to ethnicity cannot be ruled out. Of patients of African origin, 77% had undetectable viral load after 6 months of treatment, while the corresponding figures for Caucasians and Asians were 91% and 100%, respectively. Thus, we have found an overall good short-term virological outcome after the initiation of ART in a cohort of ARV-naive patients of diverse ethnic background infected with different HIV-1 genetic subtypes. In univariate analysis ethnicity, but not genetic subtype, correlated with virological response. However, the impact of ethnicity was moderate. Patients of African origin, who had the poorest outcome, showed a 77% virological response rate.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , HIV-1/classificação , Síndrome da Imunodeficiência Adquirida/microbiologia , Síndrome da Imunodeficiência Adquirida/virologia , Adulto , Contagem de Linfócito CD4 , Feminino , Genótipo , HIV-1/genética , Humanos , Masculino , Carga Viral
18.
J Clin Microbiol ; 42(10): 4788-95, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15472342

RESUMO

Chronic hepatitis B virus (HBV) infection can cause severe liver disease, including cirrhosis and hepatocellular carcinoma. Lamivudine is a relatively recent alternative to alpha interferon for the treatment of HBV infection, but unfortunately, resistance to lamivudine commonly develops during monotherapy. Lamivudine-resistant HBV mutants display specific mutations in the YMDD (tyrosine, methionine, aspartate, aspartate) motif of the viral polymerase (reverse transcriptase [rt]), which is the catalytic site of the enzyme, i.e., methionine 204 to isoleucine (rtM204I) or valine (rtM204V). The latter mutation is often accompanied by a compensatory leucine-to-methionine change at codon 180 (rtL180M). In the present study, a novel sequencing method, pyrosequencing, was applied to the detection of lamivudine resistance mutations and was compared with direct Sanger sequencing. The new pyrosequencing method had advantages in terms of throughput. Experiments with mixtures of wild-type and resistant viruses indicated that pyrosequencing can detect minor sequence variants in heterogeneous virus populations. The new pyrosequencing method was evaluated with a small number of patient samples, and the results showed that the method could be a useful tool for the detection of lamivudine resistance in the clinical setting.


Assuntos
Difosfatos/metabolismo , Farmacorresistência Viral/genética , Vírus da Hepatite B/efeitos dos fármacos , Lamivudina/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Análise de Sequência de DNA/métodos , Sequência de Bases , Hepatite B/virologia , Vírus da Hepatite B/genética , Humanos , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase
19.
J Allergy Clin Immunol ; 114(3): 561-7, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15356557

RESUMO

BACKGROUND: Bacterial signals play an important role in the maturation of the immune system. Polymorphisms in genes coding for receptors to bacterial components can alter the immune responsiveness of the host to microbial agents and may indicate the development of aberrant immune responses that are associated with immune-mediated diseases such as atopic diseases. OBJECTIVE: The study's objective was to investigate the relationship between TLR4 and CD14 gene polymorphisms, the LPS responsiveness of PBMCs, and the presence of asthma and allergic rhinoconjunctivitis in children. METHODS: The TLR4 (Asp299Gly) and CD14/-159 polymorphisms were determined in 115 Swedish children aged 8 and 14 years. LPS-induced IL-12(p70), IL-10, and IFN-gamma responses of PBMCs from 69 of the children were analyzed by means of ELISA. The levels of soluble CD14 in serum samples were analyzed by means of ELISA, and the total IgE levels were analyzed by means of UniCAP Total IgE (Pharmacia Diagnostics, Uppsala, Sweden). RESULTS: Decreased LPS-induced IL-12(p70) and IL-10 responses were associated with the TLR4 (Asp299Gly) polymorphism and independently with asthma, especially atopic asthma. The TLR4 (Asp299Gly) polymorphism was associated with a 4-fold higher prevalence of asthma in school-aged children (adjusted odds ratio 4.5, 95% CI 1.1-17.4) but not to allergic rhinoconjunctivitis. CONCLUSION: A TLR4 polymorphism modifies innate immune responses in children and may be an important determinant for the development of asthma. This may influence the outcome of intervention studies that use microbial stimuli as immune modulators.


Assuntos
Asma/genética , Interleucina-12/sangue , Lipopolissacarídeos/imunologia , Glicoproteínas de Membrana/genética , Polimorfismo Genético , Subunidades Proteicas/sangue , Receptores de Superfície Celular/genética , Adolescente , Asma/imunologia , Criança , Conjuntivite Alérgica/genética , Conjuntivite Alérgica/imunologia , Predisposição Genética para Doença , Humanos , Imunoglobulina E/sangue , Interleucina-10/sangue , Leucócitos Mononucleares/imunologia , Receptores de Lipopolissacarídeos/sangue , Receptores de Lipopolissacarídeos/genética , Ativação Linfocitária , Rinite Alérgica Sazonal/genética , Rinite Alérgica Sazonal/imunologia , Suécia , Receptor 4 Toll-Like , Receptores Toll-Like
20.
Am J Respir Crit Care Med ; 170(10): 1049-56, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15256392

RESUMO

Activated fibroblasts are suggested to be involved in the deposition of extracellular matrix in the formation of peribronchial fibrosis in asthma. We report the novel finding of activated elongated fibroblasts accompanied by elevated numbers of eosinophils in bronchoalveolar lavage fluid from 5 out of 12 patients with mild asthma (= 42%), whereas no fibroblasts were observed in the control subjects without asthma (n = 17). The elongated fibroblasts migrated twice as far when compared with fibroblasts from corresponding bronchial biopsies from the same patients, accompanied by an induced expression of RhoA and Rac1, indicating that the increased expression of these proteins are linked to increased migratory capabilities. Moreover, the elongated fibroblasts had an elevated production of the proteoglycans biglycan, versican, perlecan, and decorin, which correlated to an active cytoplasm in these cells. Differential expression patterns between the two fibroblast groups in motility-regulating proteins, such as cofilin, nuclear chloride ion channel protein, and heat-shock protein 20, were identified by two-dimensional electrophoresis and mass spectrometry. These findings indicate the presence of activated and mobile fibroblasts accompanied by an induced inflammatory response outside the airway epithelium in patients with mild asthma, results that may play a role in formation of airway fibrosis.


Assuntos
Asma/patologia , Hiper-Reatividade Brônquica/diagnóstico , Líquido da Lavagem Broncoalveolar/citologia , Fibroblastos/patologia , Adolescente , Adulto , Idoso , Asma/fisiopatologia , Biópsia por Agulha , Western Blotting , Testes de Provocação Brônquica , Movimento Celular , Células Cultivadas , Estudos de Coortes , Feminino , Fibroblastos/fisiologia , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Probabilidade , Prognóstico , Sensibilidade e Especificidade , Índice de Gravidade de Doença
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