RESUMO
Inflammasome complexes function as key innate immune effectors that trigger inflammation in response to pathogen- and danger-associated signals. Here, we report that germline mutations in the inflammasome sensor NLRP1 cause two overlapping skin disorders: multiple self-healing palmoplantar carcinoma (MSPC) and familial keratosis lichenoides chronica (FKLC). We find that NLRP1 is the most prominent inflammasome sensor in human skin, and all pathogenic NLRP1 mutations are gain-of-function alleles that predispose to inflammasome activation. Mechanistically, NLRP1 mutations lead to increased self-oligomerization by disrupting the PYD and LRR domains, which are essential in maintaining NLRP1 as an inactive monomer. Primary keratinocytes from patients experience spontaneous inflammasome activation and paracrine IL-1 signaling, which is sufficient to cause skin inflammation and epidermal hyperplasia. Our findings establish a group of non-fever inflammasome disorders, uncover an unexpected auto-inhibitory function for the pyrin domain, and provide the first genetic evidence linking NLRP1 to skin inflammatory syndromes and skin cancer predisposition.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Carcinoma/genética , Predisposição Genética para Doença , Inflamassomos/metabolismo , Ceratose/genética , Neoplasias Cutâneas/genética , Proteínas Adaptadoras de Transdução de Sinal/química , Sequência de Aminoácidos , Proteínas Reguladoras de Apoptose/química , Carcinoma/patologia , Cromossomos Humanos Par 17/genética , Epiderme/patologia , Mutação em Linhagem Germinativa , Humanos , Hiperplasia/genética , Hiperplasia/patologia , Inflamassomos/genética , Interleucina-1/metabolismo , Ceratose/patologia , Proteínas NLR , Comunicação Parácrina , Linhagem , Domínios Proteicos , Pirina/química , Transdução de Sinais , Neoplasias Cutâneas/patologia , SíndromeRESUMO
Glomerulonephritis is a common and debilitating feature of systemic lupus erythematosus (SLE). The precise immune mechanisms that drive the progression from benign autoimmunity to glomerulonephritis are largely unknown. Previous investigations have shown that a moderate increase of the innate Toll-like receptor 7 (TLR7) is sufficient for the development of nephritis. In these systems normalization of B-cell TLR7 expression or temporal depletion of plasmacytoid dendritic cells (pDCs) slow progression; however, the critical cell that is responsible for driving full immunopathology remains unidentified. In this investigation we have shown that conventional DC expression of TLR7 is essential for severe autoimmunity in the Sle1Tg7 model of SLE. We show that a novel expanding CD11b(+) conventional DC subpopulation dominates the infiltrating renal inflammatory milieu, localizing to the glomeruli. Moreover, exposure of human myeloid DCs to IFN-α or Flu increases TLR7 expression, suggesting they may have a role in self-RNA recognition pathways in clinical disease. To our knowledge, this study is the first to highlight the importance of conventional DC-TLR7 expression for kidney pathogenesis in a murine model of SLE.
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Células Dendríticas/metabolismo , Nefrite Lúpica/fisiopatologia , Receptor 7 Toll-Like/metabolismo , Regulação para Cima , Análise de Variância , Animais , Sequência de Bases , Antígeno CD11b/metabolismo , Primers do DNA/genética , Citometria de Fluxo , Perfilação da Expressão Gênica/métodos , Humanos , Processamento de Imagem Assistida por Computador , Glomérulos Renais/citologia , Glomérulos Renais/patologia , Nefrite Lúpica/metabolismo , Camundongos , Microscopia Confocal , Dados de Sequência Molecular , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Estatísticas não ParamétricasRESUMO
Basophils, a rare leukocyte population in peripheral circulation, are conventionally identified as CD45(int) CD49b(+) FcεRI(+) cells. Here, we show that basophils from blood and several organs of naïve wild-type mice express CD41, the α subunit of α(IIb)ß3 integrin. CD41 expression on basophils is upregulated after in vivo IL-3 treatment and during infection with Nippostrongylus brasiliensis (Nb). Moreover, CD41 can be used as a reliable marker for basophils, circumventing technical difficulties associated with FcεRI for basophil identification in a Nb infection model. In vitro anti-IgE cross-linking and IL-3 basophil stimulation showed that CD41 upregulation positively correlates with augmented surface expression of CD200R and increased production of IL-4/IL-13, indicating that CD41 is a basophil activation marker. Furthermore, we found that infection with Plasmodium yoelii 17X (Py17x) induced a profound basophilia and using Mcpt8(DTR) reporter mice as a basophil-specific depletion model, we verified that CD41 can be used as a marker to track basophils in the steady state and during infection. During malarial infection, CD41 expression on basophils is negatively regulated by IFN-γ and positively correlates with increased basophil IL-4 production. In conclusion, we provide evidence that CD41 can be used as both an identification and activation marker for basophils during homeostasis and immune challenge.
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Basófilos/imunologia , Malária/imunologia , Nippostrongylus/imunologia , Plasmodium yoelii/imunologia , Glicoproteína IIb da Membrana de Plaquetas/imunologia , Infecções por Strongylida/imunologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Basófilos/patologia , Feminino , Imunoglobulina E/imunologia , Interleucina-3/imunologia , Interleucina-4/imunologia , Malária/patologia , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Infecções por Strongylida/patologiaRESUMO
Migrastatin and isomigrastatin analogues have been synthesised in order to contribute to structure-activity studies on tumour cell migration inhibitors. These include macrocycles varying in ring size, functionality and alkene stereochemistry, as well as glucuronides. The synthesis work included application of the Saegusa-Ito reaction for regio- and stereoselective unsaturated macroketone formation, diastereoselective Brown allylation to generate 9-methylmigrastatin analogues and chelation-induced anomerisation to vary glucuronide configuration. Compounds were tested in vitro against both breast and pancreatic cancer cell lines and inhibition of tumour cell migration was observed in both wound-healing (scratch) and Boyden chamber assays. One unsaturated macroketone showed low affinity for a range of secondary drug targets, indicating it is at low risk of displaying adverse side effects.
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Alcenos/química , Movimento Celular/efeitos dos fármacos , Glucuronídeos/química , Compostos Macrocíclicos/química , Compostos Macrocíclicos/farmacologia , Macrolídeos/química , Macrolídeos/farmacologia , Neoplasias Pancreáticas/química , Piperidonas/química , Piperidonas/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Relação Estrutura-AtividadeRESUMO
Invited for the cover of this issue are Paulâ V. Murphy and co-workers at the National University of Ireland Galway (NUI Galway) and Warsaw University. The image depicts MGSTA-6 giving a stop signal to tumour cells that are on the move. Read the full text of the article at 10.1002/chem.201502861.
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Movimento Celular/efeitos dos fármacos , Compostos Macrocíclicos/química , Macrolídeos/síntese química , Macrolídeos/farmacologia , Piperidonas/síntese química , Piperidonas/farmacologia , Linhagem Celular Tumoral , Humanos , Macrolídeos/química , Estrutura Molecular , Piperidonas/química , Relação Estrutura-AtividadeRESUMO
Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease characterized by the production of antinuclear autoantibodies. Antinuclear autoantibody development is recognized as one of the initial stages of disease that often results in systemic inflammation, kidney disease, and death. The etiology is complex, but it is clear that innate pathways may play an important role in disease progression. Recent data have highlighted an important role for the TLR family, particularly TLR7, in both human disease and murine models. In this study, we have presented a low copy conditional TLR7 transgenic (Tg7) mouse strain that does not develop spontaneous autoimmunity. When we combine Tg7 with the Sle1 lupus susceptibility locus, the mice develop severe disease. Using the CD19(Cre) recombinase system, we normalized expression of TLR7 solely within the B cells. Using this method we demonstrated that overexpression of TLR7 within the B cell compartment reduces the marginal zone B cell compartment and increases B and T cell activation but not T follicular helper cell development. Moreover, this enhanced B cell TLR7 expression permits the specific development of Abs to RNA/protein complexes and exacerbates SLE disease.
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Autoanticorpos/biossíntese , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/patologia , Regulação da Expressão Gênica no Desenvolvimento/imunologia , Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/imunologia , Glicoproteínas de Membrana/genética , Receptor 7 Toll-Like/genética , Animais , Autoanticorpos/efeitos adversos , Subpopulações de Linfócitos B/metabolismo , Progressão da Doença , Epistasia Genética/imunologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/patologia , Masculino , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Complexos Multiproteicos/genética , Complexos Multiproteicos/imunologia , Receptor 7 Toll-Like/biossíntese , Receptor 7 Toll-Like/fisiologia , Transgenes/imunologiaRESUMO
BACKGROUND: Understanding characteristics associated with survival following esophagectomy for cancer is critical to preoperative risk stratification. This study sought to define predictors for long-term survival following esophagectomy for cancer in Medicare patients. METHODS: The STS GTSD was queried for patients age>65 who underwent esophagectomy for cancer between 2012-2020 and linked to CMS data using a deterministic matching algorithm. Patient, hospital, and treatment variables were assessed using a multivariable Cox proportional hazards model to evaluate characteristics associated with long-term mortality and readmission. Kaplan-Meier and cumulative incidence curves were generated and differences evaluated using the Log-rank test and Gray's test respectively. RESULTS: After CMS linkage, 4,798 patients were included. 30-day and 90-day mortality in the study group was 3.84% and 7.45%, respectively. In the multivariable model, ASA>3, BMI>35, and diabetes were associated with increased mortality <90 days post-surgery, while pN/pT upstaging was associated with increased mortality >90 days post-surgery. Patients upstaged to pN(+) had a 147% increased mortality risk (aHR 2.47;95%CI2.02-3.02) and those that remained pN(+) a 75% increased mortality risk (aHR 1.75;95%CI1.57-1.95) compared to down-staged patients. Patients who were pT upstaged had a 109% (aHR 2.09;95%CI1.73-2.53) increased mortality risk compared to pT downstaged patients. Risk for readmission was independent of procedure type or approach and was higher in cStage>2, ASA>4, and pN+. CONCLUSIONS: Medicare patients undergoing esophagectomy for cancer have identifiable patient-specific predictors for short-term mortality and tumor-specific predictors for long-term mortality and readmission. In the absence of pathologic T and N downstaging, risk for long-term mortality and readmission are increased.
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Lactating rats reinfected with Nippostrongylus brasiliensis fed low-crude protein (CP) foods show reduced lactational performance and less resistance to parasites compared with their high-CP counterparts. Here, we hypothesised that feeding high-CP foods deficient in specific essential amino acids (AA) would result in similar penalties. Second-parity lactating rats, immunised with 1600 N. brasiliensis infective larvae before mating, were fed foods with either 250 (high protein; HP) or 150 (low protein; LP) g CP/kg, or were HP deficient in either leucine (HP-Leu) or methionine (HP-Met). On day 1 of lactation, litter size was standardised at twelve pups. On day 2, dams were either reinfected with 1600 N. brasiliensis larvae or sham-infected with PBS. Dams and litters were weighed daily until either day 8 or 11, when worm burdens, and inflammatory cells and systemic levels of N. brasiliensis-specific Ig isotypes were assessed. Data from five out of sixteen HP-Met rats were omitted due to very high levels of food refusals from parturition onwards. Relative to feeding HP foods, feeding LP, HP-Met and HP-Leu foods reduced dam weight gain and, to a lesser extent, litter weight gain, and increased the number of worm eggs in the colon, indicative of a reduction in resistance to parasites. However, only feeding LP and HP-Leu foods resulted in increased worm numbers, while none of the feeding treatments affected systemic Ig, mast and goblet cells, and eosinophil numbers. The present results support the view that resistance to parasites during lactation may be sensitive to specific essential AA scarcity.
Assuntos
Trato Gastrointestinal/parasitologia , Imunidade nas Mucosas , Hospedeiro Imunocomprometido , Lactação/imunologia , Leucina/deficiência , Metionina/deficiência , Nippostrongylus/fisiologia , Animais , Anticorpos Anti-Helmínticos/análise , Dieta com Restrição de Proteínas/efeitos adversos , Fezes/parasitologia , Feminino , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/patologia , Lactação/sangue , Larva/imunologia , Fenômenos Fisiológicos da Nutrição Materna , Carga Parasitária , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Infecções por Strongylida/patologia , Infecções por Strongylida/prevenção & controle , Redução de PesoRESUMO
It is accepted among scholars that coping changes as people mature during adolescence, but little is known about the relationship between maturity and coping. The purpose of this paper was to assess a model, which included dispositional coping, coping effectiveness, and cognitive social maturity. We predicted that cognitive social maturity would have a direct effect on coping effectiveness, and also an indirect impact via dispositional coping. Two hundred forty-five adolescent athletes completed measures of dispositional coping, coping effectiveness, and cognitive social maturity, which has three dimensions: conscientiousness, peer influence on behavior, and rule following. Using structural equation modeling, we found support for our model, suggesting that coping is related to cognitive social maturity. This information can be used to influence the content of coping interventions for adolescents of different maturational levels.
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Adaptação Psicológica/fisiologia , Comportamento do Adolescente/psicologia , Atletas/psicologia , Cognição/fisiologia , Personalidade/fisiologia , Comportamento Social , Adolescente , Comportamento do Adolescente/fisiologia , Desenvolvimento do Adolescente/fisiologia , Afeto/fisiologia , Atletas/estatística & dados numéricos , Criança , Consciência , Feminino , Humanos , Masculino , Motivação/fisiologia , Grupo Associado , Inquéritos e QuestionáriosRESUMO
The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database continues to be one of the most comprehensive clinical outcomes registries capturing almost all pediatric cardiothoracic surgical operations undertaken in the United States. The latest analysis of aggregate outcomes was performed after the 33rd data harvest and included congenital and pediatric cardiac operations performed between July 1, 2017 and June 30, 2021. This article summarizes these contemporary outcomes and provides a context for the interpretation of these outcomes. In addition this article describes ongoing efforts to improve data collection and augment analytical approaches. Finally, research activities undertaken in the last year using data from the database are also summarized.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Cirurgiões , Cirurgia Torácica , Humanos , Estados Unidos , Criança , Cardiopatias Congênitas/cirurgia , Sociedades Médicas , Avaliação de Resultados em Cuidados de Saúde , Bases de Dados FactuaisRESUMO
The synthesis and magnetic characterisation of a series of bis-µ-alkoxide bridged Mn(III) dinuclear complexes of general formula [Mn(III)(2)(µ-OR)(2)(biphen)(2)(ROH)(x)(L)(y)] (where R = Me, Et; H(2) biphen = 2,2'-biphenol and L = terminally bonded N-donor ligand) is described, doubling the literature basis set for this type of complex. Building on these findings we have categorised all known µ-OR bridged Mn(III) dinuclear complexes into one of three classifications with respect to their molecular structures. We have then employed DFT and MO calculations to assess all potential magneto-structural correlations for this class of compound in order to identify the structural requirements for constructing ferromagnetic family members. Our analysis indicates that the most influential parameter which governs the exchange interaction in this class of compounds is the relative orientation of the JT axes of the Mn(III) â atoms. A perpendicular orientation of the JT axes leads to a large ferromagnetic contribution to the exchange. These results also suggest that a large ferromagnetic interaction and a large anisotropy are unlikely to co-exist in such structural types.
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The role of progesterone in modulating dendritic cell (DC) function following stimulation of different TLRs is relatively unknown. We compared the ability of progesterone to modulate murine bone marrow-derived DC cytokine production (IL-6 and IL-12) and costimulatory molecule expression (CD40, CD80, and CD86) induced by either TLR3 or TLR4 ligation and determined whether activity was via the progesterone receptor (PR) or glucocorticoid receptor (GR) by comparative studies with the PR-specific agonist norgestrel and the GR agonist dexamethasone. Progesterone was found to downregulate, albeit with different sensitivities, both TLR3- and TLR4-induced IL-6 production entirely via the GR, but IL-12p40 production via either the GR or PR. Of particular significance was that progesterone was able to significantly inhibit TLR3- but not TLR4-induced CD40 expression in bone marrow-derived DCs. Stimulation of the PR (with progesterone and norgestrel) by pretreatment of DCs was found to sustain IFN regulatory factor-3 phosphorylation following TLR3 ligation, but not TLR4 ligation. Overall, these studies demonstrate that progesterone can differentially regulate the signaling pathways employed by TLR3 and TLR4 agonists to affect costimulatory molecule expression and cytokine production.
Assuntos
Células Dendríticas/metabolismo , Progesterona/metabolismo , Transdução de Sinais/imunologia , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Citocinas/biossíntese , Células Dendríticas/citologia , Células Dendríticas/imunologia , Ensaio de Imunoadsorção Enzimática , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Progesterona/farmacologia , Receptores de Glucocorticoides/imunologia , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/imunologia , Receptores de Progesterona/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 3 Toll-Like/efeitos dos fármacos , Receptor 3 Toll-Like/imunologia , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/imunologiaRESUMO
BACKGROUND: To identify opportunities for enhanced data collection for adults with congenital heart disease (ACHD), a structured review of existing variables in The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database (CHSD) and the STS Adult Cardiac Surgery Database (ACSD) was conducted. METHODS: A working group was assembled representing multiple STS Workforces and Task Forces. The ACSD was reviewed systematically over eight 90-minute calls. ACSD version 4.20.2 and CHSD version 3.41 were used, and the ACSD was approached in sections. ACSD variables were classified as (1) represented in identical form in the CHSD (no further discussion), (2) represented in similar form in the CHSD (discussed for potential harmonization of definitions), or (3) not represented in the CHSD (discussed for potential inclusion). Variables felt to be relevant to ACHD were noted, and special consideration was given to STS required fields and variables used in existing STS adult risk models. Other factors that were examined were the frequency, use, and capture of existing ACSD variables. RESULTS: Over 22 weeks (8 calls), the existing 1069 variables in version 4.20.2 of the ACSD were discussed. Ultimately, 539 total variables were found to be both (1) relevant to ACHD and (2) not currently collected in the CHSD. These were recommended for inclusion in the next CHSD upgrade for patients aged ≥18 years. CONCLUSIONS: For adult patients having case records entered into the CHSD, the inclusion of a limited set of additional data fields from the ACSD should enhance capture of comorbidities and other clinical data relevant to the ACHD population.
Assuntos
Cardiopatias Congênitas , Cirurgiões , Cirurgia Torácica , Adulto , Humanos , Adolescente , Sociedades Médicas , Avaliação de Resultados em Cuidados de Saúde , Cardiopatias Congênitas/cirurgia , Bases de Dados FactuaisRESUMO
T1/ST2 is an immunoregulatory protein of the IL-1 receptor family that has recently been reported as being a component of the IL-33 receptor. IL-33 is a newly described cytokine known to amplify the Th2 response and reduce production of Th1 cytokines. The function of T1/ST2 during Toxoplasma gondii infection is as yet undescribed. Given the requirement of a balanced type 1/type 2 response for effective control of parasite number and immunopathology, it is likely that T1/ST2 may play a part in aiding this process. Accordingly, we have shown that T1/ST2 mRNA transcripts are upregulated in the brains of mice infected with T. gondii and that mice deficient in T1/ST2 demonstrated increased susceptibility to infection with T. gondii that correlated with increased pathology and greater parasite burden in the brains. Real-time PCR analysis of cerebral cytokine levels revealed increased mRNA levels of iNOS, IFN-gamma and TNF-alpha in infected T1/ST2(-/-) mice. These effects were independent of changes in IL-10 production. This study provides the first evidence of a specific role for IL-33 receptor signalling in the brain as well as highlighting the requirement of this mechanism in limiting infection with an intracellular parasite.
Assuntos
Encefalite/imunologia , Receptores de Interleucina/imunologia , Transdução de Sinais/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Animais , Peso Corporal , Encéfalo/metabolismo , Encéfalo/parasitologia , Encéfalo/patologia , Encefalite/parasitologia , Ensaio de Imunoadsorção Enzimática , Feminino , Interferon gama/genética , Interferon gama/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-4/genética , Interleucina-4/imunologia , Interleucina-4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Receptores de Superfície Celular/metabolismo , Receptores de Interleucina/genética , Receptores de Interleucina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Toxoplasma/crescimento & desenvolvimento , Toxoplasmose Animal/parasitologia , Ativação Transcricional , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Periparturient relaxation of immunity (PPRI) to parasites in mammals results in higher worm burden and worm egg excretion and may have a nutritional basis. Nippostrongylus brasiliensis re-infected lactating rats fed low-crude protein (CP) diets show an augmented degree of PPRI compared with their high CP-fed counterparts. However, such effects of CP scarcity have been confounded by metabolisable energy (ME) scarcity due to increased intake of the high-CP foods. Here, we independently assessed the effects of dietary CP and ME scarcity on the degree of PPRI. Second, parity rats were infected with N. brasiliensis larvae before mating. Upon parturition, dams were allocated to one of six feeding treatments (1-6), consisting of two levels of dietary ME supply, each with three levels of CP supply. On day 2 of lactation, dams were either re-infected with 1600 N. brasiliensis larvae or sham-infected with PBS, while litter size was standardised at ten pups. Dams and litters were weighed daily until either day 8 or 11 of lactation, when worm burdens were assessed as a proxy for PPRI. Increased CP and ME supply independently improved lactational performance. While ME supply did not affect parasitism, increasing CP supply reduced worm burden and the percentage of female worms in the small intestine; the latter was especially pronounced at the lower level of ME supply. The present results support the view that PPRI to parasites may be sensitive to CP scarcity, but not to moderate ME scarcity.
Assuntos
Proteínas Alimentares/administração & dosagem , Ingestão de Energia/imunologia , Lactação/imunologia , Lactação/fisiologia , Doenças Parasitárias em Animais/imunologia , Doenças Parasitárias em Animais/fisiopatologia , Animais , Feminino , Nippostrongylus/imunologia , Nippostrongylus/patogenicidade , Contagem de Ovos de Parasitas , Doenças Parasitárias em Animais/parasitologia , Gravidez , Ratos , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Infecções por Strongylida/fisiopatologiaRESUMO
The reaction of CuX(2) (X(-) ≠ F(-)) salts with 1 equiv of 3-pyridyl-5-tert-butylpyrazole (HL) in basic methanol yields blue solids, from which disk complexes of the type [Cu(7)(µ(3)-OH)(4)(µ-OR)(2)(µ-L)(6)](2+) and/or the cubane [Cu(4)(µ(3)-OH)(4)(HL)(4)](4+) can be isolated by recrystallization under the appropriate conditions. Two of the disk complexes have been prepared in crystalline form: [Cu(7)(µ(3)-OH)(4)(µ-OCH(2)CF(3))(2)(µ-L)(6)][BF(4)](2) (2) and [Cu(7)(µ(3)-OH)(4)(µ-OCH(3))(2)(µ-L)(6)]Cl(2)·xCH(2)Cl(2) (3·xCH(2)Cl(2)). The molecular structures of both compounds as solvated crystals can be described as [CuâCu(6)(µ-OH)(4)(µ-OR)(2)(µ-L)(6)](2+) (R = CH(2)CF(3) or CH(3)) adducts. The [Cu(6)(µ-OH)(4)(µ-OR)(2)(µ-L)(6)] ring is constructed of six square-pyramidal Cu ions, linked by 1,2-pyrazolido bridges from the L(-) ligands and by basal, apical-bridging hydroxy or alkoxy groups, while the central Cu ion is bound to the four metallamacrocyclic hydroxy donors in a near-regular square-planar geometry. The L(-) ligands project above and below the metal ion core, forming two bowl-shaped cavities that are fully (R = CH(2)CF(3)) or partially (R = CH(3)) occupied by the alkoxy R substituents. Variable-temperature magnetic susceptibility measurements on 2 demonstrated antiferromagnetic interactions between the Cu ions, yielding a spin-frustrated S = (1)/(2) magnetic ground state that is fully populated below around 15 K. Electrospray ionization mass spectrometry, UV/vis/near-IR, and electron paramagnetic resonance measurements imply that the heptacopper(II) disk motif is robust in organic solvents.
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Zinc has been demonstrated to play an important role in bone metabolism and is required for normal growth. However, no studies have investigated the influence of zinc on calvarial bone healing in aged or adult rats. The aim of the study was to evaluate whether alimentary zinc supplementation and depletion affect bone healing of calvarial defects implanted with osteopromotive substances in adult rats. Two 5 mm full thickness critical size bone defects were trephined in the central part of each parietal bone of 60 six-month-old male Wistar rats. The bone defects were filled with demineralized bone matrix (DBM), autogenous bone chips, or were left as unfilled controls. The rats were divided into three groups of 20 rats each and received a semi-synthetic diet containing 20, 60, or 120 mg zinc/kg. After 4 months, the biomechanical integrity of the healing defects was evaluated by a punch out test and the healed defects were examined with histomorphometry. Statistical analysis of the data was carried out by two-way analysis of variance and Wilcoxon's non-parametric signed rank test. Biomechanical testing revealed that the maximum load was significantly higher in DBM-filled defects than in those filled with autogenous bone, and that the defects filled with autogenous bone were stronger than the unfilled controls. The biomechanical findings indicated that the alimentary zinc content did not influence the healing of calvarial defects. No significant difference in maximum load could be established between the three diet groups for any of the filling materials, whereas the highest zinc supplement resulted in an increase in the relative extension on mineralizing surfaces in the control group. Thus, healing of adult rat calvarial defects is not influenced by alimentary zinc supplementation or depletion. Defects filled with DBM were significantly stronger and exhibited significantly more new bone formation than defects filled with autogenous bone or unfilled controls.
Assuntos
Regeneração Óssea/efeitos dos fármacos , Suplementos Nutricionais , Zinco/farmacologia , Animais , Matriz Óssea/transplante , Transplante Ósseo/métodos , Análise do Estresse Dentário , Masculino , Osso Parietal/cirurgia , Porosidade , Ratos , Ratos Wistar , Estatísticas não ParamétricasRESUMO
Although there are few high-profile cases of adolescent athletes being caught doping, up to a third of young athletes may dope. In order to generate a more accurate understanding of why adolescent athletes dope, it is important to validate models that help to explain this behavior. The aims of this study were 3-fold: firstly, to test the Sport Drug Control Model for Adolescent Athletes (SDCM-AA); secondly, to generate athlete profiles that would help quantify the proportion of athletes who are at risk of doping; and thirdly, to create norm values for the Adolescent Sport Doping Inventory (ASDI), which would allow national doping organizations, sporting organizations, and clubs to benchmark the scores of their athletes for key psycho-social variables linked to doping. A total of 2208 adolescent athletes from the United Kingdom, Australia, Hong Kong, and the United States completed the ASDI. The data presented an appropriate fit to the SDCM-AA model, in which 54% of the variance in susceptibility to doping was explained in the model, and 44.8% of attitudes toward doping was accounted for. Four distinct clusters of athletes emerged: the Susceptibles (i.e., identified with the benefits of doping, were willing to cheat, and viewed little threat), the Chancers (i.e., identified with the benefits of doping, scored high on willingness to cheat, and were highly influenced by their reference group, but had an average score for threat, self-esteem, and legitimacy), the Pragmatists (i.e., did not engage with any aspects of doping, but were more susceptible than the fair players), and Fair Players (i.e., high levels of sportspersonship, unwilling to cheat, and viewed doping as a threat). The revised SDCM-AA appears a valid model that helps explain the factors associated with doping attitudes and doping susceptibility. Adolescent athletes can be classified into one of four clusters, in relation to doping. Their cluster group could influence the content of the anti-doping education they receive.
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The preparation of a range of amino acid derived guanidine organocatalysts is reported together with their application to the Michael addition of 2-hydroxy-1,4-napthoquinone to ß-nitrostyrene, achieving a maximum ee of 56%. Some insight into the mechanism was sought by using X-ray crystallography and a detailed study of the intra- and intermolecular hydrogen bonding is reported.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.