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1.
Hist Psychiatry ; : 957154X231211727, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053372

RESUMO

Following the collapse of the Delahoyde and Lucett joint enterprise, James Lucett resumed practice on his own account. He continued to implement his 'process', promoting it as a unique cure for intractable cases of insanity. For two decades he pursued his activities, with varying success, at different locations in the London area. He maintained his public profile by extensive advertising, letters to newspapers and published pamphlets, extolling his unique 'discovery' and recounting claims of successful cures achieved. Accusations of quackery persisted along with other hostile criticism, particularly from medical men, which Lucett strongly challenged. Periodically he faced more serious difficulties due to legal infractions or financial hardships, but somehow Lucett survived most of these and persevered with his endeavours.

2.
Hist Psychiatry ; : 957154X231199352, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37941346

RESUMO

James Lucett, a London clerk, claimed possession of a secret remedy for curing chronic insanity. In 1813, he and the Irish surgeon Charles Delahoyde secured royal and aristocratic patronage to implement their 'process' and opened a private asylum. They aroused great public interest after apparently remarkable results with hitherto intractable patients from Bethlem and Hoxton. Delahoyde and Lucett attained brief celebrity, but within a year it was evident that the dramatic recoveries were only temporary. Their venture collapsed in disarray and bankruptcy, and the episode was soon largely forgotten. Delahoyde fled to Ireland, but Lucett managed to re-establish himself in practice. This article narrates the origins, operation and failure of the enterprise. A second article will consider Lucett's subsequent career.

3.
J Can Dent Assoc ; 84: j5, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31199729

RESUMO

BACKGROUND: Early childhood dental decay or caries (ECC) is common, often painful and costly to the health care system, yet it is largely preventable. A public health approach is needed, especially as socially vulnerable children most at risk for ECC are less likely to access conventional treatment. Exposure to intimate partner violence (IPV) in the family represents an important social vulnerability for children, yet little is known about ECC in this context. We explored the relation between ECC and exposure to IPV as well as opportunities for community-based early interventions to prevent ECC. METHODS: We searched 5 electronic databases. All primary research and reviews that focused on childhood decay and exposure to IPV or that referred to community settings (specifically women's shelters) for oral health service delivery were included. RESULTS: Of 198 unique documents identified, 12 were included in the analysis. Although limited, our findings suggest a positive relation between exposure to IPV and ECC, the mechanisms of which are not well studied. Women's-shelter-based prevention programs may hold promise in terms of detecting and addressing ECC. Over the time frame of the literature reviewed, we observed a subtle shift in emphasis away from individual behaviours and biological models toward upstream societal structures. CONCLUSIONS: The available literature suggests that the issue of ECC and IPV may be poised to embrace a public health approach to early intervention, characterized by community collaboration, interprofessional cooperation between dentistry and social work and an equitable approach to ECC in a socially vulnerable group.


Assuntos
Cárie Dentária , Violência por Parceiro Íntimo , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Saúde Pública
4.
Bioorg Med Chem Lett ; 27(3): 675-678, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28043798

RESUMO

Our initial discovery of 8-hydroxyquinoline inhibitors of BoNT/A and separation/testing of enantiomers of one of the more active leads indicated considerable flexibility in the binding site. We designed a limited study to investigate this flexibility and probe structure-activity relationships; utilizing the Betti reaction, a 36 compound matrix of quinolinol BoNT/A LC inhibitors was developed using three 8-hydroxyquinolines, three heteroaromatic amines, and four substituted benzaldehydes. This study has revealed some of the most effective quinolinol-based BoNT/A inhibitors to date, with 7 compounds displaying IC50 values ⩽1µM and 11 effective at ⩽2µM in an ex vivo assay.


Assuntos
Toxinas Botulínicas Tipo A/antagonistas & inibidores , Hidroxiquinolinas/química , Animais , Sítios de Ligação , Toxinas Botulínicas Tipo A/metabolismo , Hidroxiquinolinas/metabolismo , Hidroxiquinolinas/toxicidade , Concentração Inibidora 50 , Camundongos , Nervo Frênico/efeitos dos fármacos , Nervo Frênico/metabolismo , Ligação Proteica , Sorogrupo , Relação Estrutura-Atividade
5.
Med Humanit ; 43(2): 73-80, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28559363

RESUMO

Contemporary discussions around language, stigma and care in mental health, the messages these elements transmit, and the means through which they have been conveyed, have a long and deep lineage. Recognition and exploration of this lineage can inform how we communicate about mental health going forward, as reflected by the 9 papers which make up this special issue. Our introduction provides some framework for the history of communicating mental health over the past 300 years. We will show that there have been diverse ways and means of describing, disseminating and discussing mental health, in relation both to therapeutic practices and between practitioners, patients and the public. Communicating about mental health, we argue, has been informed by the desire for positive change, as much as by developments in reporting, legislation and technology. However, while the modes of communication have developed, the issues involved remain essentially the same. Most practitioners have sought to understand and to innovate, though not always with positive results. Some lost sight of patients as people; patients have felt and have been ignored or silenced by doctors and carers. Money has always talked, for without adequate investment services and care have suffered, contributing to the stigma surrounding mental illness. While it is certainly 'time to talk' to improve experiences, it is also time to change the language that underpins cultural attitudes towards mental illness, time to listen to people with mental health issues and, crucially, time to hear.


Assuntos
Transtornos Mentais , Saúde Mental/história , Estigma Social , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Serviços de Saúde Mental/história
6.
Hist Psychiatry ; 28(3): 365-377, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28776398

RESUMO

The 'mad-doctor' Dr Francis Willis achieved national and international celebrity following his successful treatment of King George III's first major episode of insanity in 1788-9. At the time of his summons to attend the King, Willis was a well-established provincial practitioner and madhouse proprietor. An anonymous French visitor published a description of Willis's Lincolnshire madhouse and his therapeutic practices in 1796. The translated text of the full article provides a unique insight into the work of a key figure in the historical development of psychological medicine. The accompanying Introduction summarizes Francis Willis's career as a mad-doctor and uses salient information from the original text to place him and his madhouse practice within a contemporary context.


Assuntos
Transtorno Bipolar/história , Transtorno Bipolar/reabilitação , Pessoas Famosas , Psiquiatria/história , França , História do Século XVIII , Humanos
7.
BMC Genomics ; 17: 180, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26939550

RESUMO

BACKGROUND: Clostridium botulinum is a diverse group of bacteria characterized by the production of botulinum neurotoxin. Botulinum neurotoxins are classified into serotypes (BoNT/A-G), which are produced by six species/Groups of Clostridia, but the genetic background of the bacteria remains poorly understood. The purpose of this study was to use comparative genomics to provide insights into the genetic diversity and evolutionary history of bacteria that produce the potent botulinum neurotoxin. RESULTS: Comparative genomic analyses of over 170 Clostridia genomes, including our draft genome assemblies for 59 newly sequenced Clostridia strains from six continents and publicly available genomic data, provided in-depth insights into the diversity and distribution of BoNT-producing bacteria. These newly sequenced strains included Group I and II strains that express BoNT/A,/B,/E, or/F as well as bivalent strains. BoNT-producing Clostridia and closely related Clostridia species were delineated with a variety of methods including 16S rRNA gene, concatenated marker genes, core genome and concatenated multi-locus sequencing typing (MLST) gene phylogenies that related whole genome sequenced strains to publicly available strains and sequence types. These analyses illustrated the phylogenetic diversity in each Group and the diversity of genomic backgrounds that express the same toxin type or subtype. Comparisons of the botulinum neurotoxin genes did not identify novel toxin types or variants. CONCLUSIONS: This study represents one of the most comprehensive analyses of whole genome sequence data for Group I and II BoNT-producing strains. Read data and draft genome assemblies generated for 59 isolates will be a resource to the research community. Core genome phylogenies proved to be a powerful tool for differentiating BoNT-producing strains and can provide a framework for the study of these bacteria. Comparative genomic analyses of Clostridia species illustrate the diversity of botulinum-neurotoxin-producing strains and the plasticity of the genomic backgrounds in which bont genes are found.


Assuntos
Toxinas Botulínicas/genética , Clostridium/genética , Hibridização Genômica Comparativa , Genoma Bacteriano , Filogenia , Técnicas de Tipagem Bacteriana , Clostridium/classificação , DNA Bacteriano/genética , Família Multigênica , Tipagem de Sequências Multilocus , Polimorfismo de Nucleotídeo Único , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Hist Psychiatry ; 27(2): 208-19, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26837815

RESUMO

Private madhouses made a significant contribution to the development of psychiatric practices in eighteenth-century England. Joseph Mason of Bristol, proprietor of a madhouse at Stapleton and then at nearby Fishponds, was part of a dynasty of successful and respected mad-doctors. A deeply religious man, his Christian ethics constituted the guiding force in his work with patients and interactions with their relatives. He was also an astute man of business, who recognized that comfortable domestic surroundings and the achievement of recoveries would enhance his reputation and attract lucrative middle-class custom. His treatment approaches, illustrated in a 1763 diary, were eclectic and pragmatic, comprising various medicines, dietary regulation, graded social interactions, and the cultivation of individualized therapeutic relationships with his patients.


Assuntos
Hospitais Psiquiátricos/história , Transtornos Mentais/história , Cristianismo/história , Inglaterra , História do Século XVIII , Humanos , Transtornos Mentais/terapia
9.
J Biol Chem ; 288(33): 24223-33, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23779108

RESUMO

Botulinum neurotoxins are the most toxic of all compounds. The toxicity is related to a poor zinc endopeptidase activity located in a 50-kDa domain known as light chain (Lc) of the toxin. The C-terminal tail of Lc is not visible in any of the currently available x-ray structures, and it has no known function but undergoes autocatalytic truncations during purification and storage. By synthesizing C-terminal peptides of various lengths, in this study, we have shown that these peptides competitively inhibit the normal catalytic activity of Lc of serotype A (LcA) and have defined the length of the mature LcA to consist of the first 444 residues. Two catalytically inactive mutants also inhibited LcA activity. Our results suggested that the C terminus of LcA might interact at or near its own active site. By using synthetic C-terminal peptides from LcB, LcC1, LcD, LcE, and LcF and their respective substrate peptides, we have shown that the inhibition of activity is specific only for LcA. Although a potent inhibitor with a Ki of 4.5 µm, the largest of our LcA C-terminal peptides stimulated LcA activity when added at near-stoichiometric concentration to three versions of LcA differing in their C-terminal lengths. The result suggested a product removal role of the LcA C terminus. This suggestion is supported by a weak but specific interaction determined by isothermal titration calorimetry between an LcA C-terminal peptide and N-terminal product from a peptide substrate of LcA. Our results also underscore the importance of using a mature LcA as an inhibitor screening target.


Assuntos
Toxinas Botulínicas Tipo A/química , Toxinas Botulínicas Tipo A/metabolismo , Domínio Catalítico , Clostridium botulinum/metabolismo , Neurotoxinas/química , Neurotoxinas/metabolismo , Sequência de Aminoácidos , Biocatálise/efeitos dos fármacos , Toxinas Botulínicas Tipo A/antagonistas & inibidores , Calorimetria , Clostridium botulinum/classificação , Estabilidade Enzimática/efeitos dos fármacos , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Ligação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína , Desdobramento de Proteína/efeitos dos fármacos , Sorotipagem , Relação Estrutura-Atividade , Especificidade por Substrato/efeitos dos fármacos , Proteína 25 Associada a Sinaptossoma/metabolismo , Temperatura
10.
Anal Chem ; 86(7): 3254-62, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24605815

RESUMO

Botulinum neurotoxins (BoNTs) are produced by various species of clostridia and are potent neurotoxins which cause the disease botulism, by cleaving proteins needed for successful nerve transmission. There are currently seven confirmed serotypes of BoNTs, labeled A-G, and toxin-producing clostridia typically only produce one serotype of BoNT. There are a few strains (bivalent strains) which are known to produce more than one serotype of BoNT, producing either both BoNT/A and /B, BoNT/A and /F, or BoNT/B and /F, designated as Ab, Ba, Af, or Bf. Recently, it was reported that Clostridium botulinum strain Af84 has three neurotoxin gene clusters: bont/A2, bont/F4, and bont/F5. This was the first report of a clostridial organism containing more than two neurotoxin gene clusters. Using a mass spectrometry based proteomics approach, we report here that all three neurotoxins, BoNT/A2, /F4, and /F5, are produced by C. botulinum Af84. Label free MS(E) quantification of the three toxins indicated that toxin composition is 88% BoNT/A2, 1% BoNT/F4, and 11% BoNT/F5. The enzymatic activity of all three neurotoxins was assessed by examining the enzymatic activity of the neurotoxins upon peptide substrates, which mimic the toxins' natural targets, and monitoring cleavage of the substrates by mass spectrometry. We determined that all three neurotoxins are enzymatically active. This is the first report of three enzymatically active neurotoxins produced in a single strain of Clostridium botulinum.


Assuntos
Toxinas Botulínicas/farmacologia , Enzimas/metabolismo , Neurotoxinas/farmacologia , Sequência de Aminoácidos , Toxinas Botulínicas/química , Toxinas Botulínicas/classificação , Espectrometria de Massas , Dados de Sequência Molecular , Neurotoxinas/química , Neurotoxinas/classificação , Isoformas de Proteínas/química , Isoformas de Proteínas/classificação , Isoformas de Proteínas/farmacologia , Proteômica , Homologia de Sequência de Aminoácidos
11.
Issues Law Med ; 29(1): 147-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25189014

RESUMO

Induced abortion is a controversial topic among obstetricians. "100 Professors" extolled the benefits of elective abortion in a Clinical Opinion published in AJOG. However, scientific balance requires the consideration of a second opinion from practitioners who care for both patients, and who recognize the humanity of both. Alternative approaches to the management of a problem pregnancy, as well as short and long term risks to women as published in the peer reviewed medical literature are discussed. Maintaining a position of "pro-choice" requires that practitioners also be given a right to exercise Hippocratic principles in accordance with their conscience.


Assuntos
Aborto Legal/estatística & dados numéricos , Ginecologia , Obstetrícia , Feminino , Humanos , Gravidez
12.
Nature ; 489(7415): 208, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22972289
13.
J AOAC Int ; 96(1): 147-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23513970

RESUMO

A recombinant ricin toxin A-chain 1-33/44-198 vaccine (RVEc), developed at the United States Army Medical Research Institute of Infectious Diseases as a vaccine candidate, is under investigation in a phase 1 clinical study. To effectively evaluate the immunogenicity of this ricin vaccine and to eliminate the use of radioactive material, an EL4 cell-based colorimetric toxin neutralization activity (TNA) assay using a CellTiter 96 AQueous One Solution Cell Proliferation Assay Reagent has been developed, optimized, and applied in the vaccine efficacy studies. The TNA assay measures the protective neutralizing anti-ricin antibodies in animal sera by determining the cell viability after ricin exposure in the assay system and comparing it to a purified mouse polyclonal antiricin IgG standard curve. The standard curve of the anti-ricin TNA assay closely fits a four-parameter logistic regression model. The unknown test sample concentration was expressed as microg/mL, but not the 50% effective concentration (EC50), which was determined by most TNA assays. The neutralizing endpoint titers, not the 50% effective dilution (ED50), of human specimens were measured with the TNA assay in support of the clinical study of the RVEc vaccine. The optimal amount of ricin toxin, EL4 cells, and concentration of standards used in the assay system was established to minimize false-negative and false-positive results of serum specimens from the nonclinical and clinical studies of RVEc. The testing conditions were adjusted to optimize assay performance. The colorimetric TNA assay replaced a radioactive TNA assay previously used in the ricin vaccine studies.


Assuntos
Anticorpos Neutralizantes/análise , Colorimetria/métodos , Ricina/imunologia , Humanos , Testes de Neutralização
14.
Anal Bioanal Chem ; 403(1): 215-26, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22395449

RESUMO

Botulinum neurotoxins (BoNTs) cause the disease botulism, which can be lethal if untreated. There are seven known serotypes of BoNT, A-G, defined by their response to antisera. Many serotypes are distinguished into differing subtypes based on amino acid sequence, and many subtypes are further differentiated into toxin variants. Previous work in our laboratory described the use of a proteomics approach to distinguish subtype BoNT/A1 from BoNT/A2 where BoNT identities were confirmed after searching data against a database containing protein sequences of all known BoNT/A subtypes. We now describe here a similar approach to differentiate subtypes BoNT/B1, /B2, /B3, /B4, and /B5. Additionally, to identify new subtypes or hitherto unpublished amino acid substitutions, we created an amino acid substitution database covering every possible amino acid change. We used this database to differentiate multiple toxin variants within subtypes of BoNT/B1 and B2. More importantly, with our amino acid substitution database, we were able to identify a novel BoNT/B subtype, designated here as BoNT/B7. These techniques allow for subtype and strain level identification of both known and unknown BoNT/B rapidly with no DNA required.


Assuntos
Toxinas Botulínicas/metabolismo , Proteômica , Sequência de Aminoácidos , Toxinas Botulínicas/química , Toxinas Botulínicas Tipo A , Dados de Sequência Molecular , Espectrometria de Massas em Tandem
15.
Aust Health Rev ; 36(1): 68-74, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22513023

RESUMO

OBJECTIVE: To assess whether Indigenous Australians age prematurely compared with other Australians, as implied by Australian Government aged care policy, which uses age 50 years and over for population-based planning for Indigenous people compared with 70 years for non-indigenous people. METHODS: Cross-sectional analysis of aged care assessment, hospital and health survey data comparing Indigenous and non-indigenous age-specific prevalence of health conditions. Analysis of life tables for Indigenous and non-indigenous populations comparing life expectancy at different ages. RESULTS: At age 63 for women and age 65 for men, Indigenous people had the same life expectancy as non-indigenous people at age 70. There is no consistent pattern of a 20-year lead in age-specific prevalence of age-associated conditions for Indigenous compared with other Australians. There is high prevalence from middle-age onwards of some conditions, particularly diabetes (type unspecified), but there is little or no lead for others. CONCLUSION: The idea that Indigenous people age prematurely is not well supported by this study of a series of discrete conditions. The current focus and type of services provided by the aged care sector may not be the best way to respond to the excessive burden of chronic disease and disability of middle-aged Indigenous people.


Assuntos
Avaliação Geriátrica , Enfermagem Geriátrica/legislação & jurisprudência , Política de Saúde , Indicadores Básicos de Saúde , Expectativa de Vida/etnologia , Havaiano Nativo ou Outro Ilhéu do Pacífico , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Estudos Transversais , Humanos , Tábuas de Vida , Pessoa de Meia-Idade
16.
Hist Psychiatry ; 23(89 Pt 1): 117-28, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22701932

RESUMO

Deaths in the asylum could be interpreted as a sign of failure, particularly if they were related to the poor condition of those admitted, the spread of disease among patients, or the direct consequences of severe mental disorders. County asylum superintendents lamented the bad physical state in which many were sent to the asylum and the consequences for death rates. Due to limited consideration of environmental and sanitary matters before the 1830s, there was great risk of contracting fatal diseases in the asylum. Combined with the deteriorated physical condition of many patients, and the growing overcrowding, this had a notable influence on mortality. For some individual patients, death came about as a direct consequence of a profound mental disorder. Without effective treatments to confront manifestations of disordered thinking, mental symptoms might precipitate physical deterioration to the point of death, while severe distress led some to kill themselves in the asylum.


Assuntos
Atitude Frente a Morte , Causas de Morte , Doenças Transmissíveis/história , Hospitais de Condado/história , Hospitais Psiquiátricos/história , Transtornos Mentais/história , Suicídio/história , Aglomeração , Inglaterra , História do Século XIX , Humanos
17.
Appl Environ Microbiol ; 77(4): 1301-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21169446

RESUMO

Botulinum neurotoxins (BoNTs) cause botulism, which can be fatal if it is untreated. BoNTs cleave proteins necessary for nerve transmission, resulting in paralysis. The in vivo protein target has been reported for all seven serotypes of BoNT, i.e., serotypes A to G. Knowledge of the cleavage sites has led to the development of several assays to detect BoNT based on its ability to cleave a peptide substrate derived from its in vivo protein target. Most serotypes of BoNT can be subdivided into subtypes, and previously, we demonstrated that three of the currently known subtypes of BoNT/F cleave a peptide substrate, a shortened version of synaptobrevin-2, between Q58 and K59. However, our research indicated that Clostridium baratii type F toxin did not cleave this peptide. In this study, we detail experiments demonstrating that Clostridium baratii type F toxin cleaves recombinant synaptobrevin-2 in the same location as that cleaved by proteolytic F toxin. In addition, we demonstrate that Clostridium baratii type F toxin can cleave a peptide substrate based on the sequence of synaptobrevin-2. This peptide substrate is an N-terminal extension of the original peptide substrate used for detection of other BoNT/F toxins and can be used to detect four of the currently known BoNT/F subtypes by mass spectrometry.


Assuntos
Proteínas de Bactérias/metabolismo , Toxinas Botulínicas/metabolismo , Clostridium/genética , Clostridium/metabolismo , Proteína 2 Associada à Membrana da Vesícula/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Clostridium botulinum tipo F/genética , Clostridium botulinum tipo F/metabolismo , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato , Proteína 2 Associada à Membrana da Vesícula/química
18.
Appl Environ Microbiol ; 77(24): 8625-34, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22003031

RESUMO

A total of 41 Clostridium botulinum serotype E strains from different geographic regions, including Canada, Denmark, Finland, France, Greenland, Japan, and the United States, were compared by multilocus sequence typing (MLST), amplified fragment length polymorphism (AFLP) analysis, variable-number tandem-repeat (VNTR) analysis, and botulinum neurotoxin (bont) E gene sequencing. The strains, representing environmental, food-borne, and infant botulism samples collected from 1932 to 2007, were analyzed to compare serotype E strains from different geographic regions and types of botulism and to determine whether each of the strains contained the transposon-associated recombinase rarA, involved with bont/E insertion. MLST examination using 15 genes clustered the strains into several clades, with most members within a cluster sharing the same BoNT/E subtype (BoNT/E1, E2, E3, or E6). Sequencing of the bont/E gene identified two new variants (E7, E8) that showed regions of recombination with other E subtypes. The AFLP dendrogram clustered the 41 strains similarly to the MLST dendrogram. Strains that could not be differentiated by AFLP, MLST, or bont gene sequencing were further examined using three VNTR regions. Both intact and split rarA genes were amplified by PCR in each of the strains, and their identities were confirmed in 11 strains by amplicon sequencing. The findings suggest that (i) the C. botulinum serotype E strains result from the targeted insertion of the bont/E gene into genetically conserved bacteria and (ii) recombination events (not random mutations) within bont/E result in toxin variants or subtypes within strains.


Assuntos
Clostridium botulinum tipo E/classificação , Clostridium botulinum tipo E/genética , DNA Bacteriano/genética , Tipagem Molecular/métodos , Polimorfismo Genético , Toxinas Botulínicas/genética , Botulismo/microbiologia , Clostridium botulinum tipo E/isolamento & purificação , Análise por Conglomerados , Elementos de DNA Transponíveis , Microbiologia Ambiental , Microbiologia de Alimentos , Genótipo , Humanos , Dados de Sequência Molecular , Recombinação Genética , Análise de Sequência de DNA
19.
BMC Biochem ; 12: 58, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22085466

RESUMO

BACKGROUND: Botulism is caused by botulinum neurotoxins (BoNTs), extremely toxic proteins which can induce respiratory failure leading to long-term intensive care or death. Treatment for botulism includes administration of antitoxins, which must be administered early in the course of the intoxication; therefore, rapid determination of human exposure to BoNT is an important public health goal. In previous work, our laboratory reported on Endopep-MS, a mass spectrometry-based activity method for detecting and differentiating BoNT/A, /B, /E, and /F in clinical samples. We also demonstrated that antibody-capture is effective for purification and concentration of BoNTs from complex matrices such as clinical samples. However, some antibodies inhibit or neutralize the enzymatic activity of BoNT, so the choice of antibody for toxin extraction is critical. RESULTS: In this work, we evaluated 24 anti-BoNT/B monoclonal antibodies (mAbs) for their ability to inhibit the in vitro activity of BoNT/B1, /B2, /B3, /B4, and /B5 and to extract those toxins. Among the mAbs, there were significant differences in ability to extract BoNT/B subtypes and inhibitory effect on BoNT catalytic activity. Some of the mAbs tested enhanced the in vitro light chain activity of BoNT/B, suggesting that BoNT/B may undergo conformational change upon binding some mAbs. CONCLUSIONS: In addition to determining in vitro inhibition abilities of a panel of mAbs against BoNT/B1-/B5, this work has determined B12.2 and 2B18.2 to be the best mAbs for sample preparation before Endopep-MS. These mAb characterizations also have the potential to assist with mechanistic studies of BoNT/B protection and treatment, which is important for studying alternative therapeutics for botulism.


Assuntos
Anticorpos Monoclonais/farmacologia , Toxinas Botulínicas/antagonistas & inibidores , Toxinas Botulínicas/isolamento & purificação , Botulismo/metabolismo , Toxinas Botulínicas/imunologia , Toxinas Botulínicas Tipo A , Botulismo/genética , Clostridium botulinum/imunologia , Clostridium botulinum/isolamento & purificação , Clostridium botulinum/metabolismo , Mapeamento de Epitopos , Humanos
20.
Protein Expr Purif ; 75(2): 177-85, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20933089

RESUMO

A purification process for the manufacture of a recombinant C-terminus heavy chain fragment from botulinum neurotoxin serotype C [rBoNTC(H(c))], a potential vaccine candidate, has been defined and successfully scaled-up. The rBoNTC(H(c)) was produced intracellularly in Pichia pastoris X-33 using a three step fermentation process, i.e., glycerol batch phase, a glycerol fed-batch phase to achieve high cell densities, followed by a methanol induction phase. The rBoNTC(H(c)) was captured from the soluble protein fraction of cell lysate using hydrophobic charge induction chromatography (HCIC; MEP HyperCel™), and then further purified using a CM 650M ion exchange chromatography step followed by a polishing step using HCIC once again. Method development at the bench scale was achieved using 5-100mL columns and the process was performed at the pilot scale using 0.6-1.6L columns in preparation for technology transfer to cGMP manufacturing. The process yielded approximately 2.5 g of rBoNTC(H(c))/kg wet cell weight (WCW) at the bench scale and 1.6 g rBoNTC(H(c))/kg WCW at the pilot scale. The purified rBoNTC(H(c)) was stable for at least 3 months at 5 and -80°C as determined by reverse phase-HPLC and SDS-PAGE and was stable for 24 months at -80 °C based on mouse potency bioassay. N-Terminal amino acid sequencing confirmed that the N-terminus of the purified rBoNTC(H(c)) was intact.


Assuntos
Toxinas Botulínicas , Clostridium botulinum/química , Pichia , Proteínas Recombinantes , Sequência de Aminoácidos , Animais , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/metabolismo , Biotecnologia , Bioterrorismo/prevenção & controle , Toxinas Botulínicas/genética , Toxinas Botulínicas/imunologia , Toxinas Botulínicas/isolamento & purificação , Toxinas Botulínicas/metabolismo , Cromatografia , Clonagem Molecular , Feminino , Fermentação , Camundongos , Dados de Sequência Molecular , Projetos Piloto , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Transferência de Tecnologia
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