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1.
PLoS One ; 19(6): e0305580, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38870257

RESUMO

People naturally exhibit a self-serving bias which can be observed in their tendency to judge their own physical attractiveness more favourably than that of others. Despite this positive self-perception, minimally invasive cosmetic injectable procedures for facial rejuvenation and enhancement are becoming increasingly common. It remains unclear, however, whether recognizing an altered version of one's own face, enhanced cosmetically, correlates with a positive view of cosmetic surgery and excessive preoccupations about physical characteristics perceived as defects (body dysmorphic concerns). In this study, 30 healthy female participants, aged 18-24 years (Mage = 21.1 years, SD = 1.6), engaged in a face recognition task during which their faces were digitally morphed with that of gender-matched unfamiliar women who had undergone cosmetic enhancements, specifically lip and cheek fillers. The duration of exposure to these modified faces varied with short (500 msec) and long (2000 msec) viewing periods. Participants were asked to identify whether the digital morphs represented themselves or the other woman. Self-reports regarding acceptance of cosmetic surgery and dysmorphic concerns were collected. Participants PSE indicated a tendency towards self-bias under short presentation times, shifting towards the other as presentation times lengthened. Interestingly, this effect was associated with greater acceptance of cosmetic surgery and higher body dysmorphic concerns. This study underscores the importance of understanding how perceptions of others' physical appearances can influence self-recognition and attitudes towards cosmetic surgery, which may have both positive and potentially harmful implications.


Assuntos
Autoimagem , Humanos , Feminino , Adulto Jovem , Adolescente , Técnicas Cosméticas/psicologia , Face , Cosméticos , Adulto , Reconhecimento Facial , Imagem Corporal/psicologia , Preenchedores Dérmicos/administração & dosagem
2.
Cancer Causes Control ; 34(Suppl 1): 217-239, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37354320

RESUMO

PURPOSE: The Cancer Prevention and Control Research Network (CPCRN) is a national network focused on accelerating the translation of cancer prevention and control research evidence into practice through collaborative, multicenter projects in partnership with diverse communities. From 2003 to 2022, the CPCRN included 613 members. METHODS: We: (1) characterize the extent and nature of collaborations through a bibliometric analysis of 20 years of Network publications; and (2) describe key features and functions of the CPCRN as related to organizational structure, productivity, impact, and focus on health equity, partnership development, and capacity building through analysis of 22 in-depth interviews and review of Network documentation. RESULTS: Searching Scopus for multicenter publications among the CPCRN members from their time of Network engagement yielded 1,074 collaborative publications involving two or more members. Both the overall number and content breadth of multicenter publications increased over time as the Network matured. Since 2004, members submitted 123 multicenter grant applications, of which 72 were funded (59%), totaling more than $77 million secured. Thematic analysis of interviews revealed that the CPCRN's success-in terms of publication and grant productivity, as well as the breadth and depth of partnerships, subject matter expertise, and content area foci-is attributable to: (1) its people-the inclusion of members representing diverse content-area interests, multidisciplinary perspectives, and geographic contexts; (2) dedicated centralized structures and processes to enable and evaluate collaboration; and (3) focused attention to strategically adapting to change. CONCLUSION: CPCRN's history highlights organizational, strategic, and practical lessons learned over two decades to optimize Network collaboration for enhanced collective impact in cancer prevention and control. These insights may be useful to others seeking to leverage collaborative networks to address public health problems.


Assuntos
Equidade em Saúde , Neoplasias , Humanos , Atenção à Saúde , Saúde Pública , Fortalecimento Institucional , Neoplasias/prevenção & controle
3.
Angew Chem Int Ed Engl ; 62(3): e202216106, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36394131

RESUMO

An amphiphilic block copolymer of polyphosphinoborane has been prepared by a mechanism-led strategy of the sequential catalytic dehydropolymerization of precursor monomers, H3 B ⋅ PRH2 (R=Ph, n-hexyl), using the simple pre-catalyst [Rh(Ph2 PCH2 CH2 PPh2 )2 ]Cl. Speciation, mechanism and polymer chain growth studies support a step-growth process where reversible chain transfer occurs, i.e. H3 B ⋅ PRH2 /oligomer/polymer can all coordinate with, and be activated by, the catalyst. Block copolymer [H2 BPPhH]110 -b-[H2 BP(n-hexyl)H]11 can be synthesized and self-assembles in solution to form either rod-like micelles or vesicles depending on solvent polarity.

4.
J Am Chem Soc ; 144(44): 20525-20538, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36306448

RESUMO

Uniform 1D block copolymer (BCP) nanofibers prepared by the seeded-growth approach termed living crystallization-driven self-assembly (CDSA) offer promising potential for various applications due to their anisotropy, length tunability, and variable core and coronal chemistries. However, this procedure consists of a multi-step process involving independent BCP synthesis and self-assembly steps, where the latter is performed at low solution concentrations (<1 wt %), hindering scale-up. Here, we demonstrate the use of a one-pot BCP synthesis and self-assembly process, polymerization-induced CDSA (PI-CDSA), to access length-disperse nanofibers with a biodegradable crystalline poly(fluorenetrimethylenecarbonate) (PFTMC) core and a hydrophilic poly(ethylene glycol) (PEG) corona derived from PEG-b-PFTMC at concentrations up to 20 wt %, 400 times higher than those previously reported. Furthermore, living PI-CDSA could be used to access scalable, low dispersity, and length-tunable 1D PEG-b-PFTMC nanofibers at concentrations of up to 10 wt %. This provides the first example of living PI-CDSA involving an all-organic and biodegradable BCP that utilizes a conveniently implemented BCP synthesis protocol and does not involve living anionic polymerization. Significantly, samples of low-dispersity nanofibers of controlled lengths from 100 to 660 nm (Lw/Ln = 1.08-1.20) were prepared, allowing for upscaled access to well-defined biodegradable nanofibers at useful length-scales for applications in nanomedicine. Interestingly, detailed studies revealed a key role for PFTMC homopolymer impurities in the BCP prepared in situ in the formation of nanofibers under the reaction conditions used.


Assuntos
Nanofibras , Cristalização , Polimerização , Nanofibras/química , Micelas , Polímeros/química , Carbonatos
5.
Vaccines (Basel) ; 8(4)2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33050254

RESUMO

: Sterne live spore vaccine (SLSV) is the current veterinary anthrax vaccine of choice. Unlike the non-living anthrax vaccine (NLAV) prototype, SLSV is incompatible with concurrent antibiotics use in an anthrax outbreak scenario. The NLAV candidates used in this study include a crude recombinant protective antigen (CrPA) and a purified recombinant protective antigen (PrPA) complemented by formalin-inactivated spores and Emulsigen-D®/Alhydrogel® adjuvants. Cattle were vaccinated twice (week 0 and 3) with NLAVs plus penicillin-G (Pen-G) treatment and compared to cattle vaccinated twice with SLSV alone and with Pen-G treatment. The immunogenicity was assessed using ELISA against rPA and FIS, toxin neutralisation assay (TNA) and opsonophagocytic assay. The protection was evaluated using an in vivo passive immunisation mouse model. The anti-rPA IgG titres for NLAVs plus Pen-G and SLSV without Pen-G treatment showed a significant increase, whereas the titres for SLSV plus Pen-G were insignificant compared to pre-vaccination values. A similar trend was measured for IgM, IgG1, and IgG2 and TNA titres (NT50) showed similar trends to anti-rPA titres across all vaccine groups. The anti-FIS IgG and IgM titres increased significantly for all vaccination groups at week 3 and 5 when compared to week 0. The spore opsonising capacity increased significantly in the NLAV vaccinated groups including Pen-G treatment and the SLSV without Pen-G but much less in the SLSV group with Pen-G treatment. Passive immunization of A/J mice challenged with a lethal dose of 34F2 spores indicated significant protective capacity of antibodies raised in the SLSV and the PrPA + FIS + adjuvants vaccinated and Pen-G treated groups but not for the NLAV with the CrPA + FIS + adjuvants and the SLSV vaccinated and Pen-G treated group. Our findings indicate that the PrPA + FIS + Emulsigen-D®/Alhydrogel® vaccine candidate may provide the same level of antibody responses and protective capacity as the SLSV. Advantageously, it can be used concurrently with Penicillin-G in an outbreak situation and as prophylactic treatment in feedlots and valuable breeding stocks.

6.
Pathogens ; 9(7)2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664259

RESUMO

The Sterne live spore vaccine (SLSV, Bacillus anthracis strain 34F2) is the veterinary vaccine of choice against anthrax though contra-indicated for use with antimicrobials. However, the use of non-living anthrax vaccine (NLAV) candidates can overcome the SLSV limitation. In this study, cattle were vaccinated with either of the NLAV (purified recombinant PA (PrPA) or crude rPA (CrPA) and formaldehyde-inactivated spores (FIS of B. anthracis strain 34F2) and emulsigen-D®/alhydrogel® adjuvants) or SLSV. The immunogenicity of the NLAV and SLSV was assessed and the protective efficacies evaluated using a passive immunization mouse model. Polyclonal IgG (including the IgG1 subset) and IgM responses increased significantly across all vaccination groups after the first vaccination. Individual IgG subsets titres peaked significantly with all vaccines used after the second vaccination at week 5 and remained significant at week 12 when compared to week 0. The toxin neutralization (TNA) titres of the NLAV vaccinated cattle groups showed similar trends to those observed with the ELISA titres, except that the former were lower, but still significant, when compared to week 0. The opsonophagocytic assay indicated good antibody opsonizing responses with 75% (PrPA+FIS), 66% (CrPA+FIS) and 80% (SLSV) phagocytosis following spores opsonization. In the passive protection test, A/J mice transfused with purified IgG from cattle vaccinated with PrPA+FIS+Emulsigen-D®/Alhydrogel® and SLSV had 73% and 75% protection from challenge with B. anthracis strain 34F2 spores, respectively, whereas IgG from cattle vaccinated with CrPA+FIS+Emulsigen-D®/Alhydrogel® offered insignificant protection of 20%. There was no difference in protective immune response in cattle vaccinated twice with either the PrPA+FIS or SLSV. Moreover, PrPA+FIS did not show any residual side effects in vaccinated cattle. These results suggest that the immunogenicity and protective efficacy induced by the NLAV (PrPA+FIS) in the cattle and passive mouse protection test, respectively, are comparable to that induced by the standard SLSV.

7.
Animals (Basel) ; 10(4)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316413

RESUMO

Ensuring high levels of welfare is imperative for modern zoos, but such organisations must also engage visitors in order to successfully spread awareness and raise conservation funds. It is therefore important to understand the responses of animals to visitor interaction to optimise welfare. Often, the opportunity to interact with humans may be enriching for animals, but in other contexts, this interaction may have negative welfare effects. We observed captive female Galápagos giant tortoises (Chelonoidis nigra) to describe aggressive interactions, characterize hierarchy using Elo ratings and assess the impact of visitor interactions. Elo ratings indicated that one individual was dominant over two equally ranked subordinates; aggressive interactions are discussed in this context. We detected significant effects of the presence of visitors and visitor type (keepers, vets or public) within the enclosure on aggression and activity. We suggest that previous miscategorisation of a natural behaviour (the finch response) as an operantly conditioned behaviour, rather than a fixed action pattern, may have triggered aggression. We then document changes made to the management of the animals to mitigate the impacts discovered. This work highlights the importance of empirical evidence in determining optimal management strategies for zoo animals with regards to public interactions and animal welfare.

8.
Toxicon ; 102: 14-24, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26004494

RESUMO

Diplodiosis, a neuromycotoxicosis of cattle and sheep grazing on mouldy cobs infected by Stenocarpella maydis, is considered the last major veterinary mycotoxicosis for which the causative mycotoxin is still unknown. The current study was aimed at characterizing the cell death observed in mouse neuroblastoma (Neuro-2a), Chinese hamster ovary (CHO-K1) and Madin-Darby bovine kidney (MDBK) cell lines exposed to the S. maydis metabolites (i.e. diplodiatoxin and dipmatol) by investigating the roles of necrosis and apoptosis. Necrosis was investigated using the lactate dehydrogenase (LDH) leakage and propidium iodide (PI) flow cytometry assays and apoptosis was evaluated using the caspase-3/7 and Annexin V flow cytometry assays. In addition, transmission electron microscopy (TEM) was used to correlate the cell death pathways observed in this study with their typical morphologies. Both diplodiatoxin and dipmatol (750 µM) induced necrosis and caspase-dependent apoptosis in Neuro-2a, CHO-K1 and MDBK cells. Ultrastructurally, the two mycotoxins induced mitochondrial damage, cytoplasmic vacuolation and nuclear fragmentation in the three cell lines. These findings have laid a foundation for future studies aimed at elucidating in detail the mechanism of action of the S. maydis metabolites.


Assuntos
Apoptose/efeitos dos fármacos , Ascomicetos/química , Células CHO/efeitos dos fármacos , Cromonas/toxicidade , Micotoxicose/etiologia , Micotoxinas/efeitos adversos , Necrose/induzido quimicamente , Animais , Bovinos , Cricetinae , Cricetulus , Camundongos , Modelos Animais , Doenças das Plantas/microbiologia , Zea mays
9.
Toxicon ; 82: 26-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24530231

RESUMO

The cytotoxicity of three Stenocarpella maydis metabolites (diplodiatoxin, dipmatol and diplonine) was investigated on Neuro-2a, CHO-K1 and MDBK cell lines. Diplodiatoxin was the most cytotoxic followed by dipmatol. Conversely, diplonine was not cytotoxic. Diplodiatoxin and dipmatol affected mitochondrial succinate dehydrogenase (MTT assay) and the overall viability of cells as assessed in real-time (xCELLigence assay). The results obtained so far indicate that diplodiatoxin and dipmatol exert their toxicity possibly via the necrotic cell death pathway.


Assuntos
Ascomicetos/metabolismo , Cromonas/toxicidade , Ciclopropanos/toxicidade , Animais , Células CHO , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromonas/metabolismo , Cricetinae , Cricetulus , Ciclopropanos/metabolismo , Cães , Cobaias , Camundongos , Mitocôndrias/metabolismo , Necrose/induzido quimicamente , Necrose/patologia , Doenças das Plantas/microbiologia , Succinato Desidrogenase/metabolismo , Zea mays
10.
Onderstepoort J Vet Res ; 81(1)2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-25686466

RESUMO

Rift Valley fever virus (RVFV) infects humans and livestock, causing haemorrhaging and abortions in animals. Three major RVF epizootics have occurred in South Africa since the 1950s and the outbreak in 2010 had a mortality rate of 10.7% in humans. Accurate and early detection is therefore essential for management of this zoonotic disease. Enzyme-linked immunosorbent assays (ELISAs) have been developed for the detection of either IgM or IgG antibodies to RVFV in animal sera. In this study, data are presented on the validation of a double-antigen ELISA for the simultaneous detection of both classes of antibodies to RVFV ina single test. ELISA plates were coated with a recombinant nucleoprotein. The nucleoprotein,conjugated to horseradish peroxidase, was used as the detecting reagent. A total of 534 sera from sheep and cattle were used in the validation. The sheep sera were collected during a RVF pathogenesis study at the Agricultural Research Council (ARC) - Onderstepoort Veterinary Institute and the cattle sera were collected during an outbreak of RVF in 2008 at the ARC -Animal Production Institute in Irene, Pretoria. The ELISA had a diagnostic sensitivity of 98.4% and a specificity of 100% when compared to a commercial cELISA. This convenient and fast assay is suitable for use in serological surveys or monitoring immune responses in vaccinated animals.


Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Febre do Vale de Rift/diagnóstico , Vírus da Febre do Vale do Rift/imunologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/virologia , Ensaio de Imunoadsorção Enzimática/métodos , Febre do Vale de Rift/imunologia , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/virologia
11.
Avian Pathol ; 42(3): 206-14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23607480

RESUMO

An ostrich farm of 929 birds that tested polymerase chain reaction-positive for highly pathogenic avian influenza H5N2 in a single sample was designated for culling, despite no evidence of sero-conversion as assessed by haemagglutination inhibition (HI) tests. A month later and immediately prior to culling, all birds were bled and tested with an IDEXX avian influenza virus (AIV) nucleoprotein (NP)-specific enzyme-linked immunosorbent assay (ELISA) and a high sero-prevalence was detected. To address the question of whether the NP-specific antibodies detected indicated exposure to H5 or non-H5 subtypes (H6N2 and H1N2 strains were also circulating regionally at the time), we developed two H5-specific ELISAs, both based on a recombinant H5 HA1 antigen. The H5 indirect ELISA used a horseradish peroxidase ostrich IgY conjugate that we produced in chicken eggs. The single-chain variable fragment (scFv) competitive ELISA (H5 scFv cELISA) used a scFv derived from an H5-immune chicken scFv library. By comparing IDEXX AIV ELISA results with those of the two H5-specific ELISAs and HI tests, we determined that up to 89% of the flock had been exposed to H5N2 AIV. We also detected evidence of suspected vaccination, since 17% of sera contained antibodies against the H5 glycoprotein but not the NP protein. Comparative analytical sensitivity indicated that HI tests are likely to miss up to 35% of H5-positive samples, and thus we consider that H5/H7-specific ELISAs should replace HI tests for ostrich testing in future.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Vírus da Influenza A Subtipo H5N2/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Struthioniformes , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Testes de Hemaglutinação/veterinária , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , África do Sul
12.
BMJ ; 344: e142; author reply e144, 2012 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-22235010
13.
J Virol Methods ; 177(2): 140-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21827790

RESUMO

The presence of competent vectors in some countries currently free of Rift Valley fever (RVF) and global changes in climate, travel and trade have increased the risk of RVF spreading to new regions and have emphasised the need for accurate and reliable diagnostic tools for early diagnosis during RVF outbreaks. Highly sensitive viral detection systems like PCR have a limited use during outbreaks because of the short duration of viraemia, whereas antibodies like specific IgM which are serological indicators of acute infection, can be detected for up to 50 days after infection. Using the highly conserved and immunogenic recombinant nucleoprotein of RVF virus in an IgM capture ELISA, the risk of laboratory infection associated with traditional serological methods is avoided. The use of pre-coated/pre-blocked ELISA plates and the conjugation of the recombinant nucleoprotein with horseradish peroxidase simplified and shortened the assay procedure. Results showed the assay to be highly reproducible with a lower detection limit equal to that of a commercial competition ELISA. By receiver operating characteristic (ROC) curve analysis the area under curve (AUC) index was determined as 1.0 and the diagnostic sensitivity and specificity at a PP cut-off value of 4.1 as 100% and 99.78% respectively. The results of this study demonstrated that the IgM capture ELISA is a safe, reliable and highly accurate diagnostic tool which can be used on its own or in parallel with other methods for the early diagnosis of RVF virus infection and also for monitoring of immune responses in vaccinated domestic ruminants.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Proteínas do Nucleocapsídeo/imunologia , Febre do Vale de Rift/diagnóstico , Vírus da Febre do Vale do Rift/isolamento & purificação , Ruminantes/virologia , Animais , Anticorpos Antivirais/imunologia , Área Sob a Curva , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática/veterinária , Soros Imunes/imunologia , Imunoglobulina M/imunologia , Gado/virologia , Proteínas Recombinantes/imunologia , Reprodutibilidade dos Testes , Febre do Vale de Rift/imunologia , Febre do Vale de Rift/veterinária , Febre do Vale de Rift/virologia , Vírus da Febre do Vale do Rift/imunologia , Vírus da Febre do Vale do Rift/patogenicidade , Ruminantes/imunologia , Sensibilidade e Especificidade
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