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1.
Artigo em Inglês | MEDLINE | ID: mdl-38362823

RESUMO

Personal self-esteem (PSE) has been well recognized as a buffer against stress; however, the effects of other types of self-esteem, such as relational self-esteem (RSE) and collective self-esteem (CSE), on stress have not been adequately explored. This study investigated the roles of PSE, RSE, and CSE in reducing stress response. The Rosenberg, Relational, and Collective Self-Esteem Scales were adopted to assess PSE, RSE, and CSE, respectively. Participants underwent an acute social stress paradigm, and their acute stress response was assessed using subjective stress reports and salivary cortisol levels. Chronic stress level was estimated using the Perceived Stress Scale and hair cortisol concentration. The results showed that PSE was negatively correlated with salivary cortisol response during acute social stress; however, no significant associations were found between any type of self-esteem and subjective stress reports. For chronic stress, all types of self-esteem were negatively associated with perceived stress level, but not with hair cortisol concentration. Further hierarchical regression analyses suggested that only PSE negatively predicted acute salivary cortisol response and perceived stress level. Overall, the findings suggest the essential role of PSE in predicting acute salivary cortisol responses and perceived stress.

2.
Commun Biol ; 6(1): 1162, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964018

RESUMO

Infectious prions consist of PrPSc, a misfolded, aggregation-prone isoform of the host's prion protein. PrPSc assemblies encode distinct biochemical and biological properties. They harbor a specific profile of PrPSc species, from small oligomers to fibrils in different ratios, where the highest infectivity aligns with oligomeric particles. To investigate the impact of PrPSc aggregate complexity on prion propagation, biochemical properties, and disease pathogenesis, we fractionated elk prions by sedimentation velocity centrifugation, followed by sub-passages of individual fractions in cervidized mice. Upon first passage, different fractions generated PrPSc with distinct biochemical, biophysical, and neuropathological profiles. Notably, low or high molecular weight PrPSc aggregates caused different clinical signs of hyperexcitability or lethargy, respectively, which were retained over passage, whereas other properties converged. Our findings suggest that PrPSc quaternary structure determines an initial selection of a specific replication environment, resulting in transmissible features that are independent of PrPSc biochemical and biophysical properties.


Assuntos
Doenças Priônicas , Príons , Camundongos , Animais , Doenças Priônicas/etiologia , Doenças Priônicas/patologia , Príons/metabolismo , Proteínas Priônicas
3.
Global Spine J ; 13(4): 995-1004, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34000874

RESUMO

STUDY DESIGN: Modified Delphi study. OBJECTIVE: The objective of this study was to establish expert consensus on the application of lateral lumbar interbody fusion (LLIF) by using the modified Delphi study. METHODS: From June 2019 to March 2020, Members of the Chinese Study Group for Lateral Lumbar Spine Surgery were selected to collect expert feedback using the modified Delphi method where 65 spine surgeons from all over China agreed to participate. Four rounds were performed: 1 face-to-face meeting and 3 subsequent survey rounds. The consensus was achieved with ≥a 70.0% agreement for each question. The recommendation of grade A was defined as ≥90.0% of the agreement for each question. The recommendation of grade B was defined as 80.0-89.9% of the agreement for each question. The recommendation of grade C was defined as 70.0-79.9% of the agreement for each question. RESULTS: A total of 65 experts formed a panelist group, and the number of questionnaires collected was 63, 59, and 62 in the 3 rounds. In total, 5 sections, 71 questions, and 382 items achieved consensus after the Delphi rounds including summary; preoperative evaluation; application at the lumbar spinal stenosis, lumbar disc herniation, lumbar spondylolisthesis, adult degenerative scoliosis, postoperative adjacent segmental degeneration, and revision surgery; complications; and postoperative follow-up evaluation of LLIF. CONCLUSION: The modified Delphi method was utilized to ascertain an expert consensus from the Chinese Study Group for Lateral Lumbar Spine Surgery to inform clinical decision-making in the application of LLIF. The salient grade A recommendations of the survey are enumerated.

4.
Prion ; 16(1): 40-57, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35634740

RESUMO

Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrPC) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrPC in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrPC than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrPC than males in the forehead and preorbital glands. The distribution of PrPC within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrPC to serve as possible sites of prion initial infection, propagation, and shedding.


Assuntos
Cervos , Príons , Órgão Vomeronasal , Doença de Emaciação Crônica , Animais , Cervos/metabolismo , Equidae/metabolismo , Feminino , Masculino , Proteínas Priônicas , Príons/metabolismo , Glândulas Odoríferas/metabolismo , Órgão Vomeronasal/metabolismo , Doença de Emaciação Crônica/metabolismo
5.
PLoS Pathog ; 17(7): e1009795, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34310662

RESUMO

Chronic wasting disease (CWD) is a prion disease affecting cervids. Polymorphisms in the prion protein gene can result in extended survival of CWD-infected animals. However, the impact of polymorphisms on cellular prion protein (PrPC) and prion properties is less understood. Previously, we characterized the effects of a polymorphism at codon 116 (A>G) of the white-tailed deer (WTD) prion protein and determined that it destabilizes PrPC structure. Comparing CWD isolates from WTD expressing homozygous wild-type (116AA) or heterozygous (116AG) PrP, we found that 116AG-prions were conformationally less stable, more sensitive to proteases, with lower seeding activity in cell-free conversion and reduced infectivity. Here, we aimed to understand CWD strain emergence and adaptation. We show that the WTD-116AG isolate contains two different prion strains, distinguished by their host range, biochemical properties, and pathogenesis from WTD-116AA prions (Wisc-1). Serial passages of WTD-116AG prions in tg(CerPrP)1536+/+ mice overexpressing wild-type deer-PrPC revealed two populations of mice with short and long incubation periods, respectively, and remarkably prolonged clinical phase upon inoculation with WTD-116AG prions. Inoculation of serially diluted brain homogenates confirmed the presence of two strains in the 116AG isolate with distinct pathology in the brain. Interestingly, deglycosylation revealed proteinase K-resistant fragments with different electrophoretic mobility in both tg(CerPrP)1536+/+ mice and Syrian golden hamsters infected with WTD-116AG. Infection of tg60 mice expressing deer S96-PrP with 116AG, but not Wisc-1 prions induced clinical disease. On the contrary, bank voles resisted 116AG prions, but not Wisc-1 infection. Our data indicate that two strains co-existed in the WTD-116AG isolate, expanding the variety of CWD prion strains. We argue that the 116AG isolate does not contain Wisc-1 prions, indicating that the presence of 116G-PrPC diverted 116A-PrPC from adopting a Wisc-1 structure. This can have important implications for their possible distinct capacities to cross species barriers into both cervids and non-cervids.


Assuntos
Proteínas Priônicas/genética , Doença de Emaciação Crônica/genética , Animais , Arvicolinae , Cricetinae , Cervos , Mesocricetus , Camundongos , Polimorfismo de Nucleotídeo Único , Doença de Emaciação Crônica/transmissão
6.
PLoS Pathog ; 17(6): e1009628, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34061899

RESUMO

Bovine spongiform encephalopathy (BSE) is a prion disease of cattle that is caused by the misfolding of the cellular prion protein (PrPC) into an infectious conformation (PrPSc). PrPC is a predominantly α-helical membrane protein that misfolds into a ß-sheet rich, infectious state, which has a high propensity to self-assemble into amyloid fibrils. Three strains of BSE prions can cause prion disease in cattle, including classical BSE (C-type) and two atypical strains, named L-type and H-type BSE. To date, there is no detailed information available about the structure of any of the infectious BSE prion strains. In this study, we purified L-type BSE prions from transgenic mouse brains and investigated their biochemical and ultrastructural characteristics using electron microscopy, image processing, and immunogold labeling techniques. By using phosphotungstate anions (PTA) to precipitate PrPSc combined with sucrose gradient centrifugation, a high yield of proteinase K-resistant BSE amyloid fibrils was obtained. A morphological examination using electron microscopy, two-dimensional class averages, and three-dimensional reconstructions revealed two structural classes of L-type BSE amyloid fibrils; fibrils that consisted of two protofilaments with a central gap and an average width of 22.5 nm and one-protofilament fibrils that were 10.6 nm wide. The one-protofilament fibrils were found to be more abundant compared to the thicker two-protofilament fibrils. Both fibrillar assemblies were successfully decorated with monoclonal antibodies against N- and C-terminal epitopes of PrP using immunogold-labeling techniques, confirming the presence of polypeptides that span residues 100-110 to 227-237. The fact that the one-protofilament fibrils contain both N- and C-terminal PrP epitopes constrains molecular models for the structure of the infectious conformer in favour of a compact four-rung ß-solenoid fold.


Assuntos
Encefalopatia Espongiforme Bovina , Modelos Moleculares , Proteínas PrPSc/química , Animais , Bovinos , Camundongos , Camundongos Transgênicos
7.
J Virol Methods ; 220: 5-12, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25869657

RESUMO

Dengue is a mosquito borne infection, which in recent years has become a major international public health concern. Annually, 100 million dengue virus infections are reported worldwide. The nonstructural protein 1 (NS1) of dengue virus is a useful target for diagnostics of dengue infection since the protein is abundantly circulating in the blood during acute phase of the disease, in both primary and secondary infections. This research paper highlights the development of a panel of Mab and bsMab for dengue NS1 detection. The P148 series of Mabs showed high specificity for recombinant dengue NS1 antigen. These antibodies showed no cross reactivity with recombinant dengue envelope protein and other viral proteins. The hybrid-hybridoma approach to generate the P156.1 and P156.2 bsMabs from the P148 monoclonal antibody method was used during this study. Furthermore, the affinity purification provided good yields of quadromas associated with HRPO in two steps. Direct detection method involved coating of plates with different concentrations of recombinant antigen and detecting with bsMab. Sensitive sandwich assay with Mabs and bsMabs was also done. Detection of nonstructural dengue antigens may be of benefit for early and rapid diagnosis of dengue infection due to their long half-life in the blood.


Assuntos
Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/isolamento & purificação , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/isolamento & purificação , Vírus da Dengue/imunologia , Proteínas não Estruturais Virais/sangue , Animais , Anticorpos Biespecíficos/genética , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/genética , Antígenos Virais/sangue , Antígenos Virais/imunologia , Dengue/diagnóstico , Feminino , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas não Estruturais Virais/imunologia
8.
PLoS One ; 7(2): e32340, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363820

RESUMO

The re-emergence of tuberculosis (TB) as a global public health threat highlights the necessity of rapid, simple and inexpensive point-of-care detection of the disease. Early diagnosis of TB is vital not only for preventing the spread of the disease but also for timely initiation of treatment. The later in turn will reduce the possible emergence of multi-drug resistant strains of Mycobacterium tuberculosis. Lipoarabinomannan (LAM) is an important non-protein antigen of the bacterial cell wall, which is found to be present in different body fluids of infected patients including blood, urine and sputum. We have developed a bispecific monoclonal antibody with predetermined specificities towards the LAM antigen and a reporter molecule horseradish peroxidase (HRPO). The developed antibody was subsequently used to design a simple low cost immunoswab based assay to detect LAM antigen. The limit of detection for spiked synthetic LAM was found to be 5.0 ng/ml (bovine urine), 0.5 ng/ml (rabbit serum) and 0.005 ng/ml (saline) and that for bacterial LAM from M. tuberculosis H37Rv was found to be 0.5 ng/ml (rabbit serum). The assay was evaluated with 21 stored clinical serum samples (14 were positive and 7 were negative in terms of anti-LAM titer). In addition, all 14 positive samples were culture positive. The assay showed 100% specificity and 64% sensitivity (95% confidence interval). In addition to good specificity, the end point could be read visually within two hours of sample collection. The reported assay might be used as a rapid tool for detecting TB in resource constrained laboratory settings.


Assuntos
Anticorpos Biespecíficos/imunologia , Técnicas de Laboratório Clínico/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Recursos em Saúde , Tuberculose/diagnóstico , Tuberculose/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Antígenos de Bactérias/imunologia , Biotina/metabolismo , Western Blotting , Bovinos , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Humanos , Limite de Detecção , Lipopolissacarídeos/imunologia , Mycobacterium tuberculosis/imunologia , Coelhos , Ratos , Sensibilidade e Especificidade , Soroalbumina Bovina/metabolismo , Coloração e Rotulagem , Tuberculose/microbiologia
9.
Bioorg Med Chem ; 17(3): 1146-51, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19157881

RESUMO

A series of 1,4- and 1,5-diaryl substituted 1,2,3-triazoles was synthesized by either Cu(I)-catalyzed or Ru(II)-catalyzed 1,3-dipolar cycloaddition reactions between 1-azido-4-methane-sulfonylbenzene 9 and a panel of various para-substituted phenyl acetylenes (4-H, 4-Me, 4-OMe, 4-NMe(2), 4-Cl, 4-F). All compounds were used in in vitro cyclooxygenase (COX) assays to determine the combined electronic and steric effects upon COX-1 and COX-2 inhibitory potency and selectivity. Structure-activity relationship studies showed that compounds having a vicinal diaryl substitution pattern showed more potent COX-2 inhibition (IC(50)=0.03-0.36 microM) compared to their corresponding 1,3-diaryl-substituted counterparts (IC(50)=0.15 to >10.0 microM). In both series, compounds possessing an electron-withdrawing group (Cl and F) at the para-position of one of the aryl rings displayed higher COX-2 inhibition potency and selectivity as determined for compounds containing electron-donating groups (Me, OMe, NMe(2)). The obtained data show, that the central carbocyclic or heterocyclic ring system as found in many COX-2 inhibitors can be replaced by a central 1,2,3-triazole unit without losing COX-2 inhibition potency and selectivity. The high COX-2 inhibition potency of some 1,2,3-triazoles having a vicinal diaryl substitution pattern along with their ease in synthesis through versatile Ru(II)-catalyzed click chemistry make this class of compounds interesting candidates for further design and synthesis of highly selective and potent COX-2 inhibitors.


Assuntos
Inibidores de Ciclo-Oxigenase/síntese química , Inibidores de Ciclo-Oxigenase/farmacologia , Triazóis/síntese química , Triazóis/farmacologia , Catálise , Cobre/química , Inibidores de Ciclo-Oxigenase/química , Concentração Inibidora 50 , Rutênio/química , Relação Estrutura-Atividade , Triazóis/química
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