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1.
J Public Health Policy ; 45(3): 552-561, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39090221

RESUMO

In 1994, the United States approved the Prostate-Specific Antigen (PSA) test as a screening tool for prostate cancer. It did so despite the test's inherent weakness: not being prostate cancer specific. Subsequent randomized trials yielded conflicting results as to its benefits. Medical guideline organizations are concerned that PSA screening results in the diagnosis and treatment of clinically indolent prostate cancer. Nevertheless, PSA screening is prevalent in North America and Europe with PSA screening increasing in other regions. We provide a critical review of the major factors that led to the prevalence of PSA screening in the United States despite the debate about its benefits. Public advocacy in favor of the test and failure of the medical community to appreciate its inherent weakness led to widespread adoption. These factors persist today. Other countries need to carefully analyze the utility of the PSA test before adopting it.


Assuntos
Detecção Precoce de Câncer , Antígeno Prostático Específico , Neoplasias da Próstata , Humanos , Antígeno Prostático Específico/sangue , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/sangue , Neoplasias da Próstata/epidemiologia , Estados Unidos/epidemiologia , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos
2.
Radiol Case Rep ; 18(4): 1452-1456, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36798062

RESUMO

Tumor-to-tumor metastasis is a rare event with meningioma as the recipient tumor accounting for 20% of the reported cases. The most common primary cancers showing this phenomenon are lung and breast cancer. Most lung cancers metastasizing to a meningioma are due to lung adenocarcinoma with the literature containing only 3 prior reports of small-cell lung cancer showing this pattern of spread. Herein, we present the case of a 67-year-old-patient with small-cell lung cancer that developed a metastasis to a meningioma.

3.
Parasit Vectors ; 15(1): 110, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35346328

RESUMO

Helminth infections impact the health of hundreds of millions of persons globally and also cause important economic losses in livestock farming. Methodological limitations as well as the low attention given to the study of helminths have impacted biological research and, thus, the procurement of accurate diagnosis and effective treatments. Understanding the biology of helminths using genomic and proteomic approaches could contribute to advances in understanding host-helminth interactions and lead to new vaccines, drugs and diagnostics. Despite the significant advances in genomics in the last decade, the lack of methodological adaptation of current transgenesis techniques has hampered the progression of post-genomic research in helminthology. However, the application of new techniques, such as CRISPR, to the study of trematodes and nematodes has opened new avenues for genome editing-powered functional genomics for these pathogens. This review summarises the historical advances in functional genomics in parasitic helminths and highlights pending limitations that will need to be overcome to deploy transgenesis tools.


Assuntos
Helmintíase , Helmintos , Nematoides , Animais , Técnicas de Transferência de Genes , Helmintíase/parasitologia , Helmintos/genética , Nematoides/genética , Proteômica
4.
Ultrasound Med Biol ; 48(6): 997-1009, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35282987

RESUMO

Ultrasonic techniques are being developed to detect changes in cancellous bone caused by osteoporosis. The goal of this study was to test the relative in vivo performance of eight backscatter parameters developed over the last several years for ultrasonic bone assessment: apparent integrated backscatter (AIB), frequency slope of apparent backscatter (FSAB), frequency intercept of apparent backscatter (FIAB), normalized mean of the backscatter difference (nMBD), normalized slope of the backscatter difference (nSBD), normalized intercept of the backscatter difference (nIBD), normalized backscatter amplitude ratio (nBAR) and backscatter amplitude decay constant (BADC). Backscatter measurements were performed on the left and right femoral necks of 80 adult volunteers (age = 25 ± 11 y) using an imaging system equipped with a convex array transducer. For comparison, additional ultrasonic measurements were performed at the left and right heel using a commercially available heel-bone ultrasonometer that measured the stiffness index. Six of the eight backscatter parameters (all but nSBD and nIBD) exhibited similar and highly significant (p < 0.000001) left-right correlations (0.51 ≤ R ≤ 0.68), indicating sensitivity to naturally occurring variations in bone tissue. Left-right correlations for the stiffness index measured at the heel (R = 0.75) were not significantly better than those produced by AIB, FSAB and FIAB. The short-term precisions of AIB, nMBD, nBAR and BADC (7.8%-11.7%) were comparable to that of the stiffness index measured with the heel-bone ultrasonometer (7.5%).


Assuntos
Colo do Fêmur , Ultrassom , Adolescente , Adulto , Densidade Óssea , Colo do Fêmur/diagnóstico por imagem , Humanos , Espalhamento de Radiação , Ultrassom/métodos , Ultrassonografia/métodos , Adulto Jovem
5.
Med Dosim ; 45(4): 309-316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32381372

RESUMO

Malfunction of both implantable cardiac pacemakers and cardioverter-defibrillators as a result of exposure to therapeutic radiation is a known risk in radiation therapy. Although guidelines are available to minimize this risk for low energy beams, the guidelines rely on the estimated doses of ionizing radiation received by the device. Implicit in this calculation is that there is minimal day-to-day movement in the position of the device. However, with the exception of the leads in some cases, the devices are not intentionally sewn to the surrounding tissue but simply placed in a pocket in the prepectoral fascial compartment. This surgical technique may allow for movement of the device which may result in differences to the actual dose received during a course of treatment. The author is unaware of prior studies that have examined this specific concern. Consequently, a total 12 patients with implantable pacemakers or cardioverter-defibrillators receiving radiotherapy were reviewed with a total of 206 daily treatment images available for analysis. Although, there was a large range in the medial-lateral and the superior-inferior position of these devices, the mean position of these devices differed only by 2 mm and 2 mm respectively when compared to the first day's images. Similarly, there was a large range in the daily rotation of the device but the mean difference in rotation was only 2 degrees in the counter-clockwise direction. However, some devices were noted to move up to 3.5 cm in the medial-lateral direction, 5.0 cm in the cranial-caudal direction, and to undergo up to 43 degrees of rotation in the counter-clockwise direction. Therefore, care must be taken when these devices are close to the edge of a treatment field.


Assuntos
Desfibriladores Implantáveis , Neoplasias Pulmonares , Marca-Passo Artificial , Humanos , Neoplasias Pulmonares/radioterapia , Planejamento da Radioterapia Assistida por Computador
6.
Prev Med Rep ; 5: 33-40, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27896041

RESUMO

The purpose of this study is to investigate how the use of flavored e-cigarettes varies between youth (12-17 years old), young adults (18-29 years old), and older adults (30 + years old). Cross-sectional surveys of school-going youth (n = 3907) and young adult college students (n = 5482) in Texas, and young adults and older adults (n = 6051) nationwide were administered in 2014-2015. Proportions and 95% confidence intervals were used to describe the percentage of e-cigarette use at initiation and in the past 30 days that was flavored, among current e-cigarette users. Chi-square tests were applied to examine differences by combustible tobacco product use and demographic factors. Most e-cigarette users said their first and "usual" e-cigarettes were flavored. At initiation, the majority of Texas school-going youth (98%), Texas young adult college students (95%), and young adults (71.2%) nationwide said their first e-cigarettes were flavored to taste like something other than tobacco, compared to 44.1% of older adults nationwide. Fruit and candy flavors predominated for all groups; and, for youth, flavors were an especially salient reason to use e-cigarettes. Among adults, the use of tobacco flavor at initiation was common among dual users (e-cigarettes + combustible tobacco), while other flavors were more common among former cigarette smokers (P = 0.03). Restricting the range of e-cigarette flavors (e.g., eliminating sweet flavors, like fruit and candy) may benefit youth and young adult prevention efforts. However, it is unclear what impact this change would have on adult smoking cessation.

7.
Eur J Clin Microbiol Infect Dis ; 35(7): 1137-49, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27180244

RESUMO

Acute undifferentiated fever (AUF) poses a diagnostic challenge due to the variety of possible aetiologies. While the majority of AUFs resolve spontaneously, some cases become prolonged and cause significant morbidity and mortality, necessitating improved diagnostic methods. This study evaluated the utility of deep sequencing in fever investigation. DNA and RNA were isolated from plasma/sera of AUF cases being investigated at Cairns Hospital in northern Australia, including eight control samples from patients with a confirmed diagnosis. Following isolation, DNA and RNA were bulk amplified and RNA was reverse transcribed to cDNA. The resulting DNA and cDNA amplicons were subjected to deep sequencing on an Illumina HiSeq 2000 platform. Bioinformatics analysis was performed using the program Kraken and the CLC assembly-alignment pipeline. The results were compared with the outcomes of clinical tests. We generated between 4 and 20 million reads per sample. The results of Kraken and CLC analyses concurred with diagnoses obtained by other means in 87.5 % (7/8) and 25 % (2/8) of control samples, respectively. Some plausible causes of fever were identified in ten patients who remained undiagnosed following routine hospital investigations, including Escherichia coli bacteraemia and scrub typhus that eluded conventional tests. Achromobacter xylosoxidans, Alteromonas macleodii and Enterobacteria phage were prevalent in all samples. A deep sequencing approach of patient plasma/serum samples led to the identification of aetiological agents putatively implicated in AUFs and enabled the study of microbial diversity in human blood. The application of this approach in hospital practice is currently limited by sequencing input requirements and complicated data analysis.


Assuntos
Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/etiologia , Febre/epidemiologia , Febre/etiologia , Sequenciamento de Nucleotídeos em Larga Escala , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/terapia , Biologia Computacional/métodos , Febre/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fluxo de Trabalho , Adulto Jovem
8.
J Helminthol ; 90(1): 39-47, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25315797

RESUMO

Here we report findings to optimize and standardize conditions to attenuate metacercariae of Opisthorchis viverrini by ionizing radiation to elicit protective immune responses to challenge infection. Metacercariae were gamma-irradiated and the ability of irradiated metacercariae to prevent patent infection of challenge metacercariae in hamsters was determined, as well as their ability to induce a host antibody response. Metacercariae irradiated in a dose-dependent manner, with 3, 5, 10, 12, 20, 25 and 50 Gray, were used to infect Syrian golden hamsters by stomach gavage to ascertain the effect of irradiation on ability of the worms to establish infection. In addition, other hamsters were infected with metacercariae irradiated with 20-50 Gray, followed by challenge with intact/wild-type (non-irradiated) metacercariae to determine the protective effect as established by the numbers of adult flukes, eggs of O. viverrini in hamster faeces and anti-O. viverrini antibody titres. Significantly fewer worms were recovered from hamsters immunized with metacercariae irradiated at 20, 25 and 50 Gray than from control hamsters infected with intact metacercariae or 0 Gray, and the worms showed damaged reproductive organs. Faecal egg numbers were decreased significantly in hamsters immunized with 25 and 50 Gray metacercariae of O. viverrini. Moreover, hamsters administered metacercariae that were protected elicited a robust, specific anti-fluke immunoglobulin G response compared to control hamsters, suggesting a role for antibody in protection elicited by radiation-attenuated metacercariae.


Assuntos
Metacercárias/efeitos da radiação , Opistorquíase/parasitologia , Opisthorchis/imunologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Cricetinae , Fezes/parasitologia , Feminino , Raios gama , Humanos , Imunização , Fígado/parasitologia , Masculino , Mesocricetus , Metacercárias/crescimento & desenvolvimento , Metacercárias/imunologia , Metacercárias/fisiologia , Opistorquíase/microbiologia , Opisthorchis/crescimento & desenvolvimento , Opisthorchis/fisiologia , Opisthorchis/efeitos da radiação , Reprodução/efeitos da radiação
9.
Parasite Immunol ; 37(6): 293-303, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25854639

RESUMO

Immunomodulatory components of helminths offer great promise as an entirely new class of biologics for the treatment of inflammatory diseases. Here, we discuss the emerging themes in helminth-driven immunomodulation in the context of therapeutic drug discovery. We broadly define the approaches that are currently applied by researchers to identify these helminth molecules, highlighting key areas of potential exploitation that have been mostly neglected thus far, notably small molecules. Finally, we propose that the investigation of immunomodulatory compounds will enable the translation of current and future research efforts into potential treatments for autoimmune and allergic diseases, while at the same time yielding new insights into the molecular interface of host-parasite biology.


Assuntos
Doenças Autoimunes/terapia , Helmintos/classificação , Animais , Asma/imunologia , Asma/terapia , Doenças Autoimunes/imunologia , Misturas Complexas , Helmintos/química , Humanos , Hipersensibilidade/imunologia , Imunomodulação , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/terapia
10.
Parasite Immunol ; 36(7): 303-12, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24749785

RESUMO

Schistosoma mansoni is a blood fluke parasite responsible for schistosomiasis. The best long-term strategy to control schistosomiasis is through immunization combined with drug treatment. In this study, we cloned, expressed and purified SmTSP-2 fused to the N- and C-terminal halves of Sm29 and tested these chimeras as vaccine candidates using an adjuvant approved to be used in humans. The results demonstrated that vaccination with SmTSP-2 fused to N- or C-terminus of Sm29-induced reduction in worm burden and liver pathology when compared to control animals. Additionally, we detected high levels of mouse-specific IgG, IgG1 and IgG2a against both chimeras and significant amounts of IFN-γ and TNF-α and no IL-4. Finally, studies with sera from patients resistant to infection and living in schistosomiasis endemic areas revealed high levels of specific IgG to both chimeras when compared to healthy individuals. In conclusion, SmTSP-2/Sm29 chimeras tested here induced partial protection against infection and might be a potential vaccine candidate.


Assuntos
Antígenos de Bactérias/imunologia , Antígenos de Helmintos/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Helminto/imunologia , Glicoproteínas de Membrana/imunologia , Schistosoma mansoni , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/prevenção & controle , Tetraspaninas/imunologia , Vacinas/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Bactérias/administração & dosagem , Antígenos de Helmintos/administração & dosagem , Proteínas de Bactérias/administração & dosagem , Ilhas de CpG , Citocinas/sangue , Feminino , Proteínas de Helminto/administração & dosagem , Humanos , Imunoglobulina G/sangue , Fígado/patologia , Glicoproteínas de Membrana/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Tetraspaninas/administração & dosagem , Vacinas/administração & dosagem
11.
Parasite Immunol ; 32(8): 549-59, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20626810

RESUMO

Hookworms are one of the most prevalent parasites of humans in developing countries, but we know relatively little about the immune response generated to hookworm infection. This can be attributed to a lack of permissive animal models and a relatively small research community compared with those of the more high-profile parasitic diseases. However, recently, research has emerged on the development of vaccines to control hookworm infection and the use of hookworm to treat autoimmune and allergic disorders, contributing to a greater understanding of the strategies used by hookworms to modulate the host's immune response. A substantial body of research on the immunobiology of hookworms originates from Australia, so this review will summarize the current status of the field with a particular emphasis on research carried out 'down under'.


Assuntos
Ancylostomatoidea/imunologia , Infecções por Uncinaria/imunologia , Animais , Austrália , Doenças Autoimunes/terapia , Pesquisa Biomédica/tendências , Humanos , Hipersensibilidade/terapia , Vacinas/imunologia
12.
Mol Biochem Parasitol ; 165(2): 95-102, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19428656

RESUMO

Members of the leucine-rich repeat protein family are involved in diverse functions including protein phosphatase 2-inhibition, cell cycle regulation, gene regulation and signalling pathways. A novel Schistosoma mansoni gene, called SmLANP, presenting homology to various genes coding for proteins that belong to the super family of leucine-rich repeat proteins, was characterized here. SmLANP was 1184bp in length as determined from cDNA and genomic sequences and encoded a 296 amino acid open reading frame that spanning from 6 to 894bp. The predicted amino acid sequence had a calculated molecular weight of 32kDa. Analysis of the predicted sequence indicated the presence of 3 leucine-rich domains (LRR) located in the N-terminal region and an aspartic acid rich region in the C-terminal end. SmLANP transcript is expressed in all stages of the S. mansoni life cycle analyzed, exhibiting the highest expression level in males. The SmLANP protein was expressed in a GST expression system and antibodies raised in mice against the recombinant protein. By immunolocalization assay, using adult worms, it was shown that the protein is mainly present in the cell nucleus through the whole body and strongly expressed along the tegument cell body nuclei of adult worms. As members of this family are usually involved in protein-protein interaction, a yeast two hybrid assay was conducted to identify putative binding partners for SmLANP. Thirty-six possible partners were identified, and a protein ATP synthase subunit alpha was confirmed by pull down assays, as a binding partner of the SmLANP protein.


Assuntos
Regulação da Expressão Gênica , Proteínas de Helminto/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Schistosoma mansoni/genética , Schistosoma mansoni/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/metabolismo , Proteínas de Helminto/química , Proteínas de Helminto/genética , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Estágios do Ciclo de Vida , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/metabolismo , Schistosoma mansoni/química , Alinhamento de Sequência , Técnicas do Sistema de Duplo-Híbrido
13.
Biotechnol Adv ; 27(4): 376-88, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19239923

RESUMO

A wide range of proteins belonging to the SCP/TAPS "family" has been described for various eukaryotic organisms, including plants and animals (vertebrates and invertebrates, such as helminths). Although SCP/TAPS proteins have been proposed to play key roles in a number of fundamental biological processes, such as host-pathogen interactions and defence mechanisms, there is a paucity of information on their genetic relationships, structures and functions, and there is no standardised nomenclature for these proteins. A detailed analysis of the relationships of members of the SCP/TAPS family of proteins, based on key protein signatures, could provide a foundation for investigating these areas. In this article, we review the current state of knowledge of key SCP/TAPS proteins of eukaryotes, with an emphasis on those from parasitic helminths, and undertake a comprehensive, systematic phylogenetic analysis of currently available full-length protein sequence data (considering characteristic protein signatures or motifs) to infer relationships and provide a framework (based on statistical support) for the naming of these proteins. This framework is intended to guide genomic and molecular biological explorations of key SCP/TAPS molecules associated with infectious diseases of plants and animals. In particular, fundamental investigations of these molecules in parasites and the integration of structural and functional data could lead to new and innovative approaches for the control of parasitic diseases, with important biotechnological outcomes.


Assuntos
Biotecnologia/métodos , Glicoproteínas/genética , Proteínas de Helminto/classificação , Proteínas de Helminto/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Animais , Teorema de Bayes , Glicoproteínas/fisiologia , Proteínas de Helminto/fisiologia , Helmintos/genética , Filogenia , Proteínas de Plantas/fisiologia , Plantas/genética , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/fisiologia
14.
Mol Cell Probes ; 23(1): 1-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18977290

RESUMO

In this study, we identified, using an established oligonucleotide microarray platform for the parasitic nematode Haemonchus contortus, transcripts that are 'conserved' between serum-activated and non-activated L3s of Ancylostoma caninum (aL3 and L3, respectively) and H. contortus by cross-species hybridization (CSH) at high stringency and conducted extensive bioinformatic analyses of the cross-hybridizing expressed sequence tags (ESTs). The microarray analysis revealed significant differential hybridization between aL3 and L3 for 32 molecules from A. caninum, of which 29 were shown to have homologues/orthologues in the free-living nematode Caenorhabditis elegans and/or A. caninum and the other three molecules had no homologues in current gene databases. 'Non-wildtype' RNAi phenotypes were recorded for 13 of the C. elegans homologues. A subset of 16 C. elegans homologues/orthologues (i.e. genes abce-1, act-2, C08H9.2, C55F2.1, calu-1, col-181, cpr-6, elo-2, asp-1, K07E3.4, rpn-2, sel-9, T28C12.4, hsb-1, Y57G11C.15 and ZK593.1) were predicted to interact genetically with a total of 156 (range 1-88) other genes. Gene ontology (GO) analysis of the interacting genes revealed that the most common subcategories were signal transduction (7%), intracellular protein transport and glycolysis (6.2%) within 'biological process'; nuclear (25.7%) and intracellular (19.8%) within 'cellular component'; and ATP-binding (14.4%) and protein-binding (8.4%) within 'molecular function'. The potential roles of key molecules in the two blood-feeding parasitic nematodes are discussed in relation to the known roles of their homologues/orthologues in C. elegans. The CSH approach used may provide a tool for the screening of genes conserved across a range of different taxa of parasites for which DNA microarray platforms are not available.


Assuntos
Ancylostoma/genética , Biologia Computacional , Evolução Molecular , Haemonchus/genética , Análise de Sequência com Séries de Oligonucleotídeos , Transcrição Gênica , Animais , Caenorhabditis elegans/genética , Sondas de DNA , Genes de Helmintos
15.
Gene ; 424(1-2): 121-9, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18718861

RESUMO

Although cytochrome c genes (cyt c) and proteins (CYT C) have been relatively well studied in mammals, very little is known about them in parasitic helminths. In the present study, we investigated this group of molecules in Haemonchus contortus (barber's pole worm) and Trichostrongylus vitrinus (black scour worm), two parasitic nematodes of small ruminants. The cyt c gene (512 bp) of H. contortus had one intron and encoded a transcript of 345 nucleotides, whilst that of T. vitrinus (792 bp) had two introns and encoded a transcript of 360 nucleotides. The transcription of cyt c in T. vitrinus was substantially greater in adult males compared with females, although no such gender-enrichment was evident in adults of H. contortus. These findings were supported at the protein level by immunoblot analyses. The inferred proteins (designated Hc-CYT C and Tv-CYT C, respectively) shared nucleotide and amino acid identities of 78% and 85%, respectively. The alignment of these and other CYT C sequences from nematodes, flatworms, insects and mammals identified conserved motifs associated with CYT C oxidase- and reductase- as well as haem-binding. One residue (histidine-26) was conserved for mammals, whereas this residue was absent from all nematodes; the functional significance of this difference is not yet known. Both phylogenetic analysis and protein modelling revealed that CYT C proteins of nematodes are structurally distinct from those of mammals and other organisms, suggesting their potential as targets for parasite intervention.


Assuntos
Citocromos c/genética , Haemonchus/genética , Proteínas de Helminto/genética , Trichostrongylus/genética , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Sequência Conservada , Citocromos c/química , Primers do DNA , Haemonchus/classificação , Proteínas de Helminto/classificação , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rúmen/parasitologia , Alinhamento de Sequência , Ovinos/parasitologia , Transcrição Gênica , Trichostrongylus/classificação
16.
Biotechnol Adv ; 26(1): 35-45, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18024057

RESUMO

Blood-feeding hookworms are parasitic nematodes of major human health importance. Currently, it is estimated that 740 million people are infected worldwide, and more than 80 million of them are severely affected clinically by hookworm disease. In spite of the health problems caused and the advances toward the development of vaccines against some hookworms, limited attention has been paid to the need for improved, practical methods of diagnosis. Accurate diagnosis and genetic characterization of hookworms is central to their effective control. While traditional diagnostic methods have considerable limitations, there has been some progress toward the development of molecular-diagnostic tools. The present article provides a brief background on hookworm disease of humans, reviews the main methods that have been used for diagnosis and describes progress in establishing polymerase chain reaction (PCR)-based methods for the specific diagnosis of hookworm infection and the genetic characterisation of the causative agents. This progress provides a foundation for the rapid development of practical, highly sensitive and specific diagnostic and analytical tools to be used in improved hookworm prevention and control programmes.


Assuntos
Ancylostomatoidea/genética , Ancylostomatoidea/isolamento & purificação , DNA de Helmintos/análise , DNA de Helmintos/genética , Infecções por Uncinaria/diagnóstico , Infecções por Uncinaria/prevenção & controle , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/tendências , Ancylostomatoidea/ultraestrutura , Animais , Variação Genética , Infecções por Uncinaria/epidemiologia , Humanos , Reação em Cadeia da Polimerase
17.
Parasitology ; 134(Pt.14): 2001-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17714602

RESUMO

A partial cDNA sequence was obtained from the human blood fluke, Schistosoma mansoni using a signal sequence trap approach. The full-length cDNA was cloned and termed Sm-7TM. The corresponding open reading frame had 7 membrane spanning domains and shared identity with a small, novel group of seven transmembrane (7TM) receptors from vertebrates and invertebrates, including the human ee3 receptor - a heptahelical protein implicated in neuronal signalling. Phylogenetic analysis of this novel family showed that the Sm-7TM ORF formed a clade with exclusively invertebrate sequences. Based on topology modelling with ee3, Sm-7TM was predicted to possess an intracellular C-terminal tail, which was expressed as a soluble thioredoxin fusion protein (Sm-7TMC) in Escherichia coli and purified using metal ion-affinity chromatography. A polyclonal antiserum against this domain was used to detect Sm-7TM in detergent-soluble parasite extracts and to immunolocalize the receptor to the tegument of adult S. mansoni.


Assuntos
Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Schistosoma mansoni/genética , Schistosoma mansoni/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA Complementar , Proteínas de Helminto/química , Proteínas de Helminto/imunologia , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Receptores de Superfície Celular/química , Receptores de Superfície Celular/imunologia
18.
Hand (N Y) ; 2(1): 12-5, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18780042

RESUMO

Epineural ganglia are considered to be a usual cause of peripheral nerve compression. In this report, we present a rare case of ulnar nerve compression by an epineural ganglion in the cubital tunnel. A 28-year-old right-handed female secretary developed progressive pain, numbness, and weakness in her right elbow, forearm, and hand for 6 months. Atrophy of the adductor pollicis and the first dorsal interosseous muscles was apparent. Clinical examination revealed a cystic mass at the posterior side of the elbow. Magnetic resonance imaging identified a ganglion while electrophysiologic studies revealed a severe conduction block of the ulnar nerve at the elbow. During surgery a 2-cm diameter epineural ganglion was identified compressing the ulnar nerve and was excised using microsurgery techniques. Two months postoperatively, the clinical recovery of the patient was very satisfactory, although the postoperative electrophysiologic studies demonstrated a less dramatic improvement.

19.
Parasitology ; 134(Pt 3): 427-36, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17109779

RESUMO

Hookworms feed on blood, utilizing haemoglobin for nutrition, growth and reproduction. The haemoglobin digestion cascade has been partially elucidated, but the process immediately preceding this event, haemolysis, has received considerably less attention. We have cloned and expressed Ancylostoma caninum mRNAs encoding 2 proteins belonging to the saposin-like protein (SAPLIP) family, termed Ac-slp-1 and Ac-slp-2. The open reading frames of SLP-1 and SLP-2 were used to identify expressed sequence tags encoding SAPLIPs from the 4 major clades of animal parasitic nematodes. Both Ac-slp-1 and slp-2 mRNAs were shown to be expressed in all life stages assessed, with slp-1 predominantly being expressed in third-stage larvae (L3) before and after activation with dog serum. Recombinant SLP-1 and SLP-2 were expressed in insect cells and used to raise specific antisera in mice. These antisera were used as probes in fluorescence microscopy to localize the anatomic expression sites of both proteins to small, punctate organelles or vesicles within the intestinal cells of adult worms; weak staining was detected on the microvillar brush border of the intestine. Using transmission electron microscopy, both proteins were localized to similar vesicles in the intestinal cells of the L3. Recombinant proteins contained C-terminal purification tags that potentially precluded dimerization and possibly interfered with the subsequent detection of haemolytic activity. Their expression in the gut of the L3 and adult stages suggests a role for these hookworm SAPLIPs in the lysis of host cells during tissue migration and/or feeding.


Assuntos
Ancylostoma/metabolismo , Mucosa Intestinal/metabolismo , Saposinas , Sequência de Aminoácidos , Ancylostoma/genética , Ancylostoma/crescimento & desenvolvimento , Animais , Cães , Proteínas de Helminto/química , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Intestinos/ultraestrutura , Camundongos , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saposinas/química , Saposinas/genética , Saposinas/metabolismo , Análise de Sequência de DNA
20.
Int J Parasitol ; 36(6): 701-10, 2006 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-16545815

RESUMO

The gastrointestinal tracts of multi-cellular blood-feeding parasites are targets for vaccines and drugs. Recently, recombinant vaccines that interrupt the digestion of blood in the hookworm gut have shown efficacy, so we explored the intestinal transcriptomes of the human and canine hookworms, Necator americanus and Ancylostoma caninum, respectively. We used Laser Microdissection Microscopy to dissect gut tissue from the parasites, extracted the RNA and generated cDNA libraries. A total of 480 expressed sequence tags were sequenced from each library and assembled into contigs, accounting for 268 N. americanus genes and 276 A. caninum genes. Only 17% of N. americanus and 36% of A. caninum contigs were assigned Gene Ontology classifications. Twenty-six (9.8%) N. americanus and 18 (6.5%) A. caninum contigs did not have homologues in any databases including dbEST-of these novel clones, seven N. americanus and three A. caninum contigs had Open Reading Frames with predicted secretory signal peptides. The most abundant transcripts corresponded to mRNAs encoding cholesterol-and fatty acid-binding proteins, C-type lectins, Activation-Associated Secretory Proteins, and proteases of different mechanistic classes, particularly astacin-like metallopeptidases. Expressed sequence tags corresponding to known and potential recombinant vaccines were identified and these included homologues of proteases, anti-clotting factors, defensins and integral membrane proteins involved in cell adhesion.


Assuntos
Ancylostoma/genética , Genes de Helmintos , Mucosa Intestinal/metabolismo , Necator americanus/genética , Sequência de Aminoácidos , Ancylostoma/anatomia & histologia , Ancylostoma/imunologia , Ancylostoma/metabolismo , Animais , Antígenos de Helmintos/imunologia , DNA Complementar/genética , DNA de Helmintos/genética , Ingestão de Alimentos/genética , Etiquetas de Sequências Expressas , Biblioteca Gênica , Humanos , Microdissecção , Microscopia Confocal , Dados de Sequência Molecular , Necator americanus/anatomia & histologia , Necator americanus/imunologia , Necator americanus/metabolismo , Fases de Leitura Aberta , RNA de Helmintos/genética , RNA Mensageiro/genética , Alinhamento de Sequência
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