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1.
Anaesthesia ; 78(6): 758-769, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36633911

RESUMO

Maternal critical care is a developing area of clinical practice. Looking after a critically ill woman requires a multidisciplinary team that must endeavour to maintain the relative normality of pregnancy. Whilst consideration of the fetus should be taken when making clinical decisions regarding maternal care, unfounded concerns for the fetus can contribute to therapeutic inertia such that potentially life-saving therapies are denied to pregnant women. The management of a critically ill obstetric patient must reflect, as closely as possible, the management of critical illness outside pregnancy. We will discuss some of the current evidence and concepts around this emerging area in obstetrics, including enhanced maternity care, maternal medicine networks and clinical care.


Assuntos
Serviços de Saúde Materna , Obstetrícia , Feminino , Gravidez , Humanos , Estado Terminal/terapia , Cuidados Críticos , Feto
2.
J Intensive Care Soc ; 23(2): 222-232, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35615234

RESUMO

Hyperosmolar solutions are widely used to treat raised intracranial pressure following severe traumatic brain injury. Although mannitol has historically been the most frequently administered, hypertonic saline solutions are increasingly being used. However, definitive evidence regarding their comparative effectiveness is lacking. The Sugar or Salt Trial is a UK randomised, allocation concealed open label multicentre pragmatic trial designed to determine the clinical and cost-effectiveness of hypertonic saline compared with mannitol in the management of patients with severe traumatic brain injury. Patients requiring intensive care unit admission and intracranial pressure monitoring post-traumatic brain injury will be allocated at random to receive equi-osmolar boluses of either mannitol or hypertonic saline following failure of routine first-line measures to control intracranial pressure. The primary outcome for the study will be the Extended Glasgow Outcome Scale assessed at six months after randomisation. Results will inform current clinical practice in the routine use of hyperosmolar therapy as well as assess the impact of potential side effects. Pre-planned longer term clinical and cost effectiveness analyses will further inform the use of these treatments.

3.
Rev Neurol ; 72(5): 151-156, 2021 Mar 01.
Artigo em Espanhol | MEDLINE | ID: mdl-33616197

RESUMO

INTRODUCTION: The Wada test consists of the selective and reversible inhibition of a cerebral hemisphere by intracarotid injection of amobarbital in order to evaluate the laterality of language and memory. However, there are other anesthetic drugs such as propofol, as an alternative for the test. OBJECTIVE: The objective of the study was to describe the tolerability and adverse effects (AE) of the use of propofol for the Wada test, during the presurgical study of patients with drug-resistant epilepsy. METHODS: Consecutive patients with a diagnosis of drug-resistant structural epilepsy were selected who underwent the Wada test during the pre-surgical study in the period from June 2012 to May 2019. The patients were retrospectively evaluated. The AE were described according to the Mikuni classification, modified by Curot. The variables of sex, age, epileptic foci laterality, language laterality, lesional substrate, etiology and dose of administered Propofol were analyzed for any statistical significance. RESULTS: A total of 74 patients, 40 men (54%), were studied. Forty-seven patients (63.5%) had at least one AE. The mean dose of propofol was 9.23 mg. The most frequent AE were tearing, sweating and red eye, corresponding to group I (57%). One patient developed convulsive status epilepticus, an important AE not previously described during the Wada test. CONCLUSION: Performing the Wada test with propofol causes frequent mild adverse effects, which do not prevent its completion. We describe a case of convulsive status epilepticus as the only serious AE.


TITLE: Tolerabilidad y efectos adversos del propofol en la prueba de Wada.Introducción. La prueba de Wada consiste en la inhibición selectiva y reversible de un hemisferio cerebral mediante la inyección intracarotídea de amobarbital con el objetivo de evaluar la lateralidad del lenguaje y la memoria. Existen otros fármacos anestésicos, como el propofol, como alternativa para la prueba. Objetivo. El objetivo del estudio fue describir la tolerabilidad y los efectos adversos (EA) del uso de propofol para la prueba de Wada durante el estudio prequirúrgico de pacientes con epilepsia farmacorresistente. Pacientes y métodos. Se seleccionó a pacientes con diagnóstico de epilepsia estructural farmacorresistente consecutivos, quienes se sometieron a la prueba de Wada durante el estudio prequirúrgico en el período de junio de 2012 a mayo de 2019. Los pacientes fueron evaluados de manera retrospectiva. Los EA se describieron según la clasificación de Mikuni, modificada por Curot. Se analizaron las variables de sexo, edad, lateralidad del foco epiléptico, lateralidad del lenguaje, sustrato lesional, etiología y dosis de propofol administrada en busca de significación estadística. Resultados. Se estudió a un total de 74 pacientes, de los cuales 40 eran hombres (54%). Cuarenta y siete pacientes (63,5%) tuvieron al menos un EA. La dosis media de propofol fue de 9,23 mg. Los EA más frecuentes fueron lagrimeo, sudoración y ojo rojo, correspondientes al grupo I (57%). Un paciente desarrolló estado epiléptico convulsivo, EA importante no descrito anteriormente durante la prueba de Wada. Conclusión. La realización de la prueba de Wada con propofol ocasiona frecuentes efectos adversos leves, los cuales no impiden su finalización. Describimos un caso de estado epiléptico convulsivo como único EA grave.


Assuntos
Anestésicos Intravenosos/efeitos adversos , Testes Neuropsicológicos , Propofol/efeitos adversos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
4.
Plasmid ; 100: 22-30, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30336162

RESUMO

In the present study we report the identification of a sul3-associated class 1 integron containing the dfrA12-orfF-aadA2-cmlA1-aadA1-qacH array embedded in a Tn21-derived element that is part of a conjugative FII plasmid named pST1007-1A. The plasmid was identified in the Salmonella Typhimurium strain ST1007, a member of a clinically relevant clonal MDR lineage diffuse in Italy. ST1007 exhibited resistance to ampicillin, chloramphenicol, streptomycin, sulphamethoxazole, tetracycline and trimethoprim encoded by blaTEM-1, cmlA1, (aadA1, aadA2, strAB), (sul2, sul3), tet(B) and dfrA12 genes, respectively. Apart from pST1007-1A, ST1007 also harbours two chromosome-integrated resistance units RU1 (blaTEM-1-sul2-strAB) and RU2 (tet(B)), flanked by IS26 elements. RU1 and RU2 were able to move as translocatable units, respectively TU1 and TU2, and integrate via IS26 mediated recombination into pST1007-1A. A family of conjugative plasmids, harbouring different sets of antimicrobial resistance genes (ARG) was then generated: pST1007-1B (dfrA12-aadA2-cmlA1-aadA1-sul3- tet(B)), pST1007-1C (dfrA12-aadA2-cmlA1-aadA1-sul3-blaTEM-1-sul2-strAB), pST1007-1D (blaTEM-1-sul2-strAB), pST1007-1E (tet(B)) and pST1007-1F (dfrA12-aadA2-cmlA1-aadA1-sul3- tet(B) -blaTEM-1-sul2-strAB). pST1007-1A is also a mosaic plasmid containing two distinct DNA fragments acquired from I1 plasmids through recombination within the repA4, rfsF and repeat-3 sites. This study further highlights the role played by IS26 in intracellular ARGs shuffling. Moreover, attention has been focused on recombination hot spots that might play a key role in generating mosaic plasmids.


Assuntos
Farmacorresistência Bacteriana/genética , Genoma Bacteriano , Integrons , Plasmídeos/química , Salmonella typhimurium/genética , Antibacterianos/farmacologia , Mapeamento Cromossômico , Conjugação Genética , Replicação do DNA , Elementos de DNA Transponíveis , Óperon , Plasmídeos/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/metabolismo
5.
Pediatr Obes ; 13(12): 803-811, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30160046

RESUMO

BACKGROUND: Children born small for gestational age (SGA) are at increased risk of metabolic dysfunction. Dysregulation of specific microRNAs (miRNAs) contributes to aberrant gene expression patterns underlying metabolic dysfunction. OBJECTIVE: We aimed to determine and compare circulating miRNA (c-miRNA) profile of SGA and appropriate for gestational age (AGA) children with obesity and with normal weight, in order to identify biomarkers for early detection of increased risk of developing metabolic dysfunction in SGA and AGA children with obesity. METHODS: Small non-coding RNAs from serum of 15 SGA children with obesity (OB-SGA), 10 SGA children with normal weight (NW-SGA), 17 AGA children with obesity (OB-AGA) and 12 AGA children with normal weight (NW-AGA) (mean age 11.2 ± 2.6) have been extracted and sequenced in order to detect and quantify miRNA expression profiles. RESULTS: RNA-seq analyses showed 28 miRNAs dysregulated in OB-SGA vs. NW-SGA and 19 miRNAs dysregulated in OB-AGA vs. NW-AGA. Among these, miR-92a-3p, miR-122-5p, miR-423-5p, miR-484, miR-486-3p and miR-532-5p were up regulated, and miR-181b-5p was down regulated in both OB-SGA and OB-AGA compared with normal weight counterparts. Pathway analysis and miRNA target prediction suggested that these miRNAs were particularly involved in insulin signalling, glucose transport, insulin resistance, cholesterol and lipid metabolism. CONCLUSION: We identified a specific profile of c-miRNAs in SGA and AGA children with obesity compared with SGA and AGA children with normal weight. These c-miRNAs could represent specific biomarkers for early detection of increased risk of developing metabolic dysfunction in SGA and AGA children with obesity.


Assuntos
Biomarcadores/metabolismo , MicroRNA Circulante/metabolismo , Recém-Nascido Pequeno para a Idade Gestacional/metabolismo , Obesidade Infantil/metabolismo , Adolescente , Antropometria , Criança , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional/sangue , Masculino , Obesidade Infantil/sangue , Obesidade Infantil/genética , Projetos Piloto , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA
6.
Sci Rep ; 7(1): 8262, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28811613

RESUMO

Nickel acts as cofactor for a number of enzymes of many bacteria species. Its homeostasis is ensured by proteins working as ion efflux or accumulation systems. These mechanisms are also generally adopted to counteract life-threatening high extra-cellular Ni2+ concentrations. Little is known regarding nickel tolerance in the genus Sphingobium. We studied the response of the novel Sphingobium sp. ba1 strain, able to adapt to high Ni2+ concentrations. Differential gene expression in cells cultured in 10 mM Ni2+, investigated by RNA-seq analysis, identified 118 differentially expressed genes. Among the 90 up-regulated genes, a cluster including genes coding for nickel and other metal ion efflux systems (similar to either cnrCBA, nccCBA or cznABC) and for a NreB-like permease was found. Comparative analyses among thirty genomes of Sphingobium species show that this cluster is conserved only in two cases, while in the other genomes it is partially present or even absent. The differential expression of genes encoding proteins which could also work as Ni2+-accumulators (HupE/UreJ-like protein, NreA and components of TonB-associated transport and copper-homeostasis systems) was also detected. The identification of Sphingobium sp. ba1 strain adaptive mechanisms to nickel ions, can foster its possible use for biodegradation of poly-aromatic compounds in metal-rich environments.


Assuntos
Níquel/efeitos adversos , Sphingomonadaceae/efeitos dos fármacos , Sphingomonadaceae/genética , Biodegradação Ambiental , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de RNA , Sphingomonadaceae/crescimento & desenvolvimento , Sphingomonadaceae/metabolismo , Transcriptoma
7.
Plasmid ; 89: 22-26, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27916622

RESUMO

The IncQ is a group of non-conjugative but mobilisable plasmids that are found and stably maintained in a wide range of bacteria contributing to the spread of antimicrobial resistance genes and to the insurgence of multidrug resistant bacteria. Here we report the identification, in clinical Salmonella Typhimurium strains, of an IncQ1 plasmid (pNUC) which confers resistance to sulfamethoxazole, streptomycin and tetracycline through the presence of sul2, strAB and tetA genes, respectively. pNUC was detected in five multidrug resistant S. Typhimurium strains collected in Southern Italy from various hospitals and years of isolation. Bioinformatics analyses highlighted the presence of pNUC-like plasmids in pathogenic bacteria of various Enterobacteriaceae genera or species. Taken as a whole, these plasmids constitute a novel group of IncQ1 plasmids that might have originated through recombination events between a tetR-tetA gene cluster (possibly derived from a Tn1721) and a recipient IncQ1 plasmid related to RSF1010. Our findings raise concerns regarding the possible contribution of the newly identified group of IncQ1 plasmids to the spread of tetracycline resistance.


Assuntos
Farmacorresistência Bacteriana Múltipla , Plasmídeos/genética , Antibacterianos/farmacologia , Antiporters/genética , Proteínas de Bactérias/genética , Biologia Computacional/métodos , Conjugação Genética , Ordem dos Genes , Transferência Genética Horizontal , Genes Bacterianos , Testes de Sensibilidade Microbiana , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Resistência a Tetraciclina/genética
9.
Public Health Nutr ; 14(10): 1702-13, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21486521

RESUMO

OBJECTIVE: To assess the available data on the prevalence of metabolic syndrome (MS) in Latin-American countries. DESIGN: Systematic review. Searches were carried out in PubMed, ISIWeb, SCielo and Redalyc, using 'metabolic syndrome x' and 'prevalence' as keywords for titles and/or abstracts. Articles selected were cross-sectional studies in Latin-American countries, whose main objective was to study MS and whose study population is described below. MS must be determined using Adult Treatment Panel III criteria. Twelve studies with these criteria were selected, one of which was multi-centric. SETTING: Latin America. SUBJECTS: Apparently healthy subjects aged 18-65 years (including young adult, mature adult and elderly populations) of both genders. RESULTS: The general prevalence (weighted mean) of MS in Latin-American countries was 24·9 (range: 18·8-43·3) %. MS was slightly more frequent in women (25·3 %) than in men (23·2 %), and the age group with the highest prevalence of MS consisted of those over 50 years of age. The most frequent components of MS were low HDL cholesterol levels (62·9 %) and abdominal obesity (45·8 %). Similar outcomes were obtained from the multi-centre study on Latin-American populations analysed. CONCLUSIONS: The present review brings us closer to an understanding of the prevalence of MS in Latin-American countries. However, it is not possible to know the full scope of the problem, partly because data from some countries are not available, and because the methodological differences among the studies published up to the present limit a joint analysis of their results.


Assuntos
Síndrome Metabólica/epidemiologia , Adolescente , Adulto , Idoso , HDL-Colesterol/sangue , Feminino , Humanos , América Latina/epidemiologia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Obesidade Abdominal/epidemiologia , Prevalência , Fatores de Risco , Adulto Jovem
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(2 Pt 2): 026404, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21405915

RESUMO

We have calculated the viscosity and self-diffusion coefficients of plutonium in the liquid phase using quantum molecular dynamics (QMD) and in the dense-plasma phase using orbital-free molecular dynamics (OFMD), as well as in the intermediate warm dense matter regime with both methods. Our liquid metal results for viscosity are about 40% lower than measured experimentally, whereas a previous calculation using an empirical interatomic potential (modified embedded-atom method) obtained results 3-4 times larger than the experiment. The QMD and OFMD results agree well at the intermediate temperatures. The calculations in the dense-plasma regime for temperatures from 50 to 5000 eV and densities about 1-5 times ambient are compared with the one-component plasma (OCP) model, using effective charges given by the average-atom code INFERNO. The INFERNO-OCP model results agree with the OFMD to within about a factor of 2, except for the viscosity at temperatures less than about 100 eV, where the disagreement is greater. A Stokes-Einstein relationship of the viscosities and diffusion coefficients is found to hold fairly well separately in both the liquid and dense-plasma regimes.

11.
Emerg Med J ; 27(3): 235-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20304900

RESUMO

Craniopharyngiomas are reported to be the commonest non-glial tumours of childhood. The classic presentation is typically progressive, commonly manifested as visual field defects, growth abnormalities and/or endocrine disturbance. We report a case of an 11-year-old girl presenting in acute confusional state, with few historical factors suggestive of an intracranial mass lesion and no objective localising signs on examination. Although initially treated as encephalitis, neuroimaging revealed a large craniopharyngioma with acute hydrocephalus and bilateral frontal lobe compression. She was transferred immediately to the local neurosurgical unit and underwent reservoir drainage of the cystic tumour within 24 h. This resulted in immediate symptomatic resolution. This case highlights the importance of early cerebral imaging in the paediatric patient with diagnostic uncertainty and suggests a high index of suspicion for space-occupying lesions in children, despite perceived duration of symptoms.


Assuntos
Craniofaringioma/diagnóstico , Encefalite/diagnóstico , Neoplasias Hipofisárias/diagnóstico , Criança , Confusão/etiologia , Craniofaringioma/complicações , Craniofaringioma/cirurgia , Diagnóstico Diferencial , Emergências , Feminino , Cefaleia/etiologia , Humanos , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/cirurgia , Tomografia Computadorizada por Raios X
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(3 Pt 2): 036404, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21230193

RESUMO

We have calculated viscosity and mutual diffusion of deuterium-tritium (DT) in the warm, dense matter regime for densities from 5 to 20 g/cm{3} and temperatures from 2 to 10 eV, using both finite-temperature Kohn-Sham density-functional theory molecular dynamics (QMD) and orbital-free molecular dynamics (OFMD). The OFMD simulations are in generally good agreement with the benchmark QMD results, and we conclude that the simpler OFMD method can be used with confidence in this regime. For low temperatures (3 eV and below), one-component plasma (OCP) model simulations for diffusion agree with the QMD and OFMD calculations, but deviate by 30% at 10 eV. In comparison with the QMD and OFMD results, the OCP viscosities are not as good as for diffusion, especially for 5 g/cm{3} where the temperature dependence is significantly different. The QMD and OFMD reduced diffusion and viscosity coefficients are found to depend largely, though not completely, only on the Coulomb coupling parameter Γ , with a minimum in the reduced viscosity at Γ≈25 , approximately the same position found in the OCP simulations. The QMD and OFMD equations of state (pressure) are also compared with the hydrogen two-component plasma model.

14.
Emerg Med J ; 26(1): 70-1, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19104111

RESUMO

Atraumatic clostridial myonecrosis is a rare but potentially life-threatening infective condition which is thought to occur in elderly and immunocompromised subjects via bacterial translocation through the gut wall and distant haematological seeding. Previous case reports have mainly focused on an association with malignancy and bowel inflammation. The case is reported of an 84-year-old woman initially treated for cardiac chest pain, with a medical history comprising only of type 2 diabetes, hypertension and monoclonal gammopathy of unknown significance. Chest pain remains a common presentation to all emergency departments worldwide and, with increasing pressure for early intervention in cardiac causes, prehospital treatment is becoming more commonplace. Clinicians must be sure to make a thorough initial assessment and take care when prescribing cardiac medications for chest pain, owing to the vast spectrum of differential diagnoses.


Assuntos
Dor no Peito/microbiologia , Infecções por Clostridium/diagnóstico , Clostridium septicum , Músculo Esquelético/patologia , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Necrose/microbiologia
15.
Phys Rev Lett ; 101(18): 183002, 2008 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-18999826

RESUMO

Recent experiments on double photoionization of H2 with photon energies between 160 and 240 eV have revealed body-frame angular distributions that suggest classical two-slit interference effects may be present when one electron carries most of the available energy and the second electron is not observed. We report precise quantum mechanical calculations that reproduce the experimental findings. They reveal that the interpretation in terms of classical diffraction is only appropriate at substantially higher photon energies. At the energies considered in the experiment we offer an alternative explanation based on the mixing of two nondiffractive contributions by circularly polarized light.

17.
Phys Rev Lett ; 98(7): 073001, 2007 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-17359020

RESUMO

We examine the origin of recently observed variations with internuclear distance (R) of the fully differential cross sections for double ionization of aligned H2 by absorption of a single photon. Using the results of fully converged numerical solutions of the Schrödinger equation, we show that these variations arise primarily from pronounced differences in the R dependence of the parallel and perpendicular components of the ionization amplitude. We also predict that R dependences should be readily observable in the asymmetry parameter for photodouble ionization, even in experimental measurements that are not differential in the energy sharings between ejected photoelectrons.

18.
Phys Rev Lett ; 96(7): 075506, 2006 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-16606108

RESUMO

The adsorption of carbon dimers on carbon nanotubes leads to a rich spectrum of structures and electronic structure modifications. Barriers for the formation of carbon dimer induced defects are calculated and found to be considerably lower than those for the Stone-Wales defect. The electronic states introduced by the ad-dimers depend on defect structure and tube type and size. Multiple carbon ad-dimers provide a route to structural engineering of patterned tubes that may be of interest for nanoelectronics.

19.
Intern Med J ; 34(12): 668-76, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15610211

RESUMO

BACKGROUND: Claims have been made that breast augmentation induces a previously unrecognized disease ("silicone-osis"). AIMS: To confirm the existence of "silicone-osis", qualify and quantify its characteristics. METHODS: In this population-based retrospective cohort study, the health status of 458 female Sydney residents who had augmentation mammoplasty for cosmetic reasons ("augmentation mammoplasty-exposed" or "exposed" cohort) between 1979 and 1983 was compared with the health status of 687 female Sydney residents who had non-silicone-associated plastic surgery ("augmentation mammoplasty-nonexposed" or "non-exposed" cohort). Both groups were matched for age (+/- 5 years), year of plastic surgery (+/- 2 years), plastic surgeon, anaesthetist and mode of anaesthesia. Outcome measures comprised dummy symptoms to assess reporting bias, as well as symptoms and symptom clusters from a comprehensive 78-symptom list. RESULTS: Dummy variables were not over-reported by the exposed cohort. The following individual symptoms developed more commonly in the exposed cohort after index plastic surgery: "memory loss/confusion", "altered bowel habit", "chest pain made worse by deep breathing", "shortness of breath after walking up 10 steps", "breast pain", "sweating mainly at night" and "tunnel vision". Of eight identified symptom clusters, three were rejected as biologically unimportant: "joint swelling of the bunion joint", "haemorrhoids" and "breast lumps" (the latter two occurring more commonly in the non-exposed cohort). In contrast, five symptom clusters were thought to have potential biological importance and occurred more commonly in the exposed cohort. The symptom "night sweats" was common to all five clusters, and comprised the sole symptom in one instance. The other four multisymptom clusters were also characterized by "low energy" (lethargy) and "pins and needles", whereas "breast pain", "impaired memory", "muscle pain" and "reflux", occurred in three of the four clusters. CONCLUSION: Cluster analysis suggested the existence of a multisystem disorder occurring more commonly in the exposed cohort and characterized by night sweats, lethargy, breast pain, impaired mentation, reflux, paraesthesiae, hand muscle weakness and myalgia. The argument against this being a new disease entity --"silicone-osis"-- however, was its presence, albeit at lower frequency, in the silicone-unexposed cohort. Thus this study did not confirm the existence of a new disease entity "silicone-osis" uniquely and causally associated with silicone exposure. The possible interpretations of these findings are discussed.


Assuntos
Implantes de Mama/efeitos adversos , Doenças do Tecido Conjuntivo/etiologia , Mamoplastia , Géis de Silicone/efeitos adversos , Doenças Autoimunes/etiologia , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Análise Multivariada , Estudos Retrospectivos , Inquéritos e Questionários , Saúde da Mulher
20.
Parasitology ; 129(Pt 1): 1-18, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15267107

RESUMO

Cryptosporidium parvum is a protozoan parasite that causes widespread diarrhoeal disease in humans and other animals and is responsible for large waterborne outbreaks of cryptosporidiosis. Unlike many organisms belonging to the phylum Apicomplexa, such as Plasmodium spp. and Toxoplasma gondii, there is no clinically proven drug treatment against this parasite. Aspects of the basic biology of C. parvum remain poorly understood, including a detailed knowledge of key metabolic pathways, its genome organization and organellar complement. Previous studies have proposed that C. parvum lacks a relic plastid organelle, or 'apicoplast', but that it may possess a mitochondrion. Here we characterize a mitochondrion-like organelle in C. parvum by (i) ultrastructural and morphological description (ii) localization of heterologous mitochondrial chaperonin antibody probes (iii) phylogenetic analysis of genes encoding mitochondrial transport proteins (iv) identification and analysis of mitochondrion-associated gene sequences. Our descriptive morphological analysis was performed by energy-filtering transmission electron microscopy (EFTEM) of C. hominis and C. parvum. The 'mitochondrion-like' organelle was characterized by labelling the structure with a heterologous mitochondrial chaperonin probe (hsp60) both in immunoelectron microscopy (IMEM) and immunofluorescence (IMF). Phylogenetic analysis of the mitochondrial import system and housekeeping components (hsp60 and hsp70-dnaK) suggested that the C. parvum mitochondrion-like organelle is likely to have descended from a common ancestral apicomplexan mitochondrion. We also identified a partial cDNA sequence coding for an alternative oxidase (AOX) gene, a component of the electron transport chain which can act as an alternative to the terminal mitochondrial respiratory complexes III and IV, which has not yet been reported in any other member of this phylum. Degenerate primers developed to identify selected mitochondrial genes failed to identify either cytochrome oxidase subunit I, or cytochrome b. Taken together, our data aim to provide new insights into the characterization of this Cryptosporidium organelle and a logical framework for future functional investigation.


Assuntos
Cryptosporidium parvum/ultraestrutura , Mitocôndrias/ultraestrutura , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/química , Proteínas de Transporte/genética , Chaperonina 60/metabolismo , Clonagem Molecular , Cryptosporidium parvum/genética , Cryptosporidium parvum/metabolismo , DNA de Protozoário/química , DNA de Protozoário/genética , Corantes Fluorescentes/química , Indóis/química , Microscopia Eletrônica , Microscopia de Fluorescência , Mitocôndrias/metabolismo , Modelos Biológicos , Dados de Sequência Molecular , Compostos Orgânicos , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência
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