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1.
Mol Cell ; 75(4): 791-806.e8, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31303470

RESUMO

YAP/TEAD are nuclear effectors of the Hippo pathway, regulating organ size and tumorigenesis largely through promoter-associated function. However, their function as enhancer regulators remains poorly understood. Through an in vivo proximity-dependent labeling (BioID) technique, we identified YAP1 and TEAD4 protein as co-regulators of ERα on enhancers. The binding of YAP1/TEAD4 to ERα-bound enhancers is augmented upon E2 stimulation and is required for the induction of E2/ERα target genes and E2-induced oncogenic cell growth. Furthermore, their enhancer binding is a prerequisite for enhancer activation marked by eRNA transcription and for the recruitment of the enhancer activation machinery component MED1. The binding of TEAD4 on active ERE-containing enhancers is independent of its DNA-binding behavior, and instead, occurs through protein-tethering trans-binding. Our data reveal a non-canonical function of YAP1 and TEAD4 as ERα cofactors in regulating cancer growth, highlighting the potential of YAP/TEAD as possible actionable drug targets for ERα+ breast cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/metabolismo , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Estrogênios/farmacologia , Proteínas Musculares/metabolismo , Proteínas de Neoplasias/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas de Ligação a DNA/genética , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Células MCF-7 , Subunidade 1 do Complexo Mediador/genética , Subunidade 1 do Complexo Mediador/metabolismo , Camundongos , Camundongos Nus , Proteínas Musculares/genética , Proteínas de Neoplasias/genética , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
2.
Int J Mol Sci ; 24(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36982614

RESUMO

Only few allergens derived from house dust mite (HDM) species have been evaluated in terms of their potential to induce allergic inflammation. In this study, we aimed to evaluate different aspects of the allergenicity and allergenic activity of Blo t 2, a Blomia tropicalis allergen. Blo t 2 was produced as a recombinant protein in Escherichia coli. Its allergenic activity was tested in humans by skin prick test and basophil activation assays, and in mice, by passive cutaneous anaphylaxis and a model of allergic airway inflammation. Sensitization rate to Blo t 2 (54.3%) was similar to that found to Blo t 21 (57.2%) and higher than to Der p 2 (37.5%). Most Blo t 2-sensitized patients showed a low intensity response (99.5%). Blo t 2 elicited CD203c upregulation and allergen induced skin inflammation. Additionally, immunized animals produced anti-Blo t 2 IgE antibodies and passive transfer of their serum to non-immunized animals induced skin inflammation after allergen exposure. Immunized animals developed bronchial hyperreactivity and a strong inflammatory lung reaction (eosinophils and neutrophils). These results confirm the allergenic activity of Blo t 2 and supports its clinical relevance.


Assuntos
Alérgenos , Pyroglyphidae , Humanos , Camundongos , Animais , Dermatophagoides pteronyssinus , Imunoglobulina E , Inflamação , Antígenos de Dermatophagoides
3.
J Psycholinguist Res ; 51(6): 1347-1370, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35871210

RESUMO

Recent work has shown significant sublexical effects of long-term memory in nonword repetition (NWR) using a dichotomous consonant age of acquisition (CAoA) variable (Moore, 2018; Moore, Fiez, and Tompkins, 2017). Performance consistently decreased when stimuli comprised consonants acquired later versus earlier in speech development. To address potential confounds related to stimulus design and linearity, the purpose of this study was to test whether performance decreases as the CAoA value of stimuli increases in various linguistic tasks using a continuous CAoA variable. Thirty-one college students completed NWR and other linguistic tasks in which the stimuli varied in average CAoA values. Data were analyzed using multilevel modeling. After accounting for phonotactic probability, CAoA was a statistically significant predictor of performance across the models reported. The relationship was more complex in some of the models in which CAoA showed a statistically significant nonlinear relationship with the outcome measure. Results from this study support previous work showing that CAoA affects performance on NWR and other linguistic tasks that vary in their memory, auditory perceptual, and articulatory demands. Importantly, this line of work was extended here by demonstrating that the CAoA effect is robust across novel stimulus sets and study designs, and may be more complex than previously understood when using a dichotomous CAoA variable. Quadratic results suggest that the CAoA variable has a differential effect on performance for low to moderate CAoA values, but for higher CAoA values the effect is similarly negative. The nonlinear relationship between CAoA and measures of speed and accuracy on some of the tasks warrants further study into the complex relationship between various predictive factors that contribute to language performance.


Assuntos
Desenvolvimento da Linguagem , Linguística , Humanos , Testes de Linguagem , Idioma , Memória de Longo Prazo , Fonética
4.
Int Arch Allergy Immunol ; 182(10): 971-979, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34091446

RESUMO

INTRODUCTION: Cross-reactivity between shrimp and house dust mite (HDM) proteins has been widely documented. In tropical region, shrimp (5-15%) and mite sensitization (80-95%) is prevalent in allergic patients. However, the clinical relevance of shrimp sensitization in patients with allergic rhinitis (AR) has been poorly studied. The aim of this study was to determine the prevalence and the clinical relevance shrimp IgE sensitization in AR patients sensitized to Dermatophagoides pteronyssinus. METHODS: The study was conducted in Medellin (Colombia). A cross-sectional study in patients with AR sensitized to HDM was performed in 3 steps: (i) assessment of IgE sensitization frequency to shrimp Penaeus azteca, Litopenaeus vannamei, and tropomyosin homologous allergens rDer p 10, rPen a 1, and rLit v 1, (ii) evaluation of the clinical relevance of shrimp sensitization using oral challenge test (OCT) and (iii) identification of possible risk factors for positive-OCT results. Ethical committee approval was obtained. RESULTS: From 443 patients with AR, 86 (19.4%) were sensitized to shrimp and 23 of them (26.7%) had shrimp allergy diagnosis. Thirty-six of the patients sensitized to shrimp (41.2%) reported not previously consumed this food and eleven of them had a positive-OCT (30.5%). There was not statistically significant difference in total IgE or sIgE (D. pteronyssinus, P. azteca, L. vannamei, rPen a 1, and rLit v 1) between OCT groups (positive vs. negative results). Anti-Der p 10 IgE was associated with risk for a positive-OCT in different multivariable scenarios. DISCUSSION/CONCLUSION: Our results suggest that in patients with HDM-associated AR and shrimp IgE sensitization is necessary to evaluate the clinical relevance of shrimp IgE even if the patient has never consumed shrimp because of cross-reactivity. Anti-Der p 10 could be a possible biomarker of clinical relevance to shrimp sensitization and could reduce the need for OCTs.


Assuntos
Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/imunologia , Hipersensibilidade Alimentar/imunologia , Imunoglobulina E/sangue , Penaeidae/imunologia , Rinite Alérgica/imunologia , Tropomiosina/imunologia , Adulto , Alérgenos/imunologia , Animais , Reações Cruzadas , Estudos Transversais , Feminino , Hipersensibilidade Alimentar/sangue , Humanos , Imunoglobulina E/imunologia , Testes Imunológicos , Masculino , Pessoa de Meia-Idade , Rinite Alérgica/sangue , Método Simples-Cego , Adulto Jovem
5.
Synapse ; 75(2): e22186, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32780904

RESUMO

Metabolic syndrome (MS) results from excessive consumption of high-calorie foods and sedentary lifestyles. Clinically, insulin resistance, abdominal obesity, hyperglycemia, dyslipidemia, and hypertension are observed. MS has been considered a risk factor in the development of dementia. In the brain, a metabolically impaired environment generates oxidative stress and excessive production of pro-inflammatory cytokines that deteriorate the morphology and neuronal function in the hippocampus, leading to cognitive impairment. Therapeutic alternatives suggest that phenolic compounds can be part of the treatment for neuropathies and metabolic diseases. In recent years, the use of Gallic Acid (GA) has demonstrated antioxidant and anti-inflammatory effects that contribute to neuroprotection and memory improvement in animal models. However, the effect of GA on hippocampal neurodegeneration and memory impairment under MS conditions is still unclear. In this work, we administered GA (20 mg/kg) for 60 days to rats with MS. The results show that GA treatment improved zoometric and biochemical parameters, as well as the recognition memory, in animals with MS. Additionally, GA administration increased hippocampal dendritic spines and decreased oxidative stress and inflammation. Our results show that GA treatment improves metabolism: reducing the oxidative and inflammatory environment that facilitates the recovery of the neuronal morphology in the hippocampus of rats with MS. Consequently, the recognition of objects by these animals, suggesting that GA could be used therapeutically in metabolic disorders that cause dementia.


Assuntos
Ácido Gálico/farmacologia , Hipocampo/efeitos dos fármacos , Síndrome Metabólica/metabolismo , Reconhecimento Psicológico/efeitos dos fármacos , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Catalase/efeitos dos fármacos , Catalase/metabolismo , Dendritos/efeitos dos fármacos , Dendritos/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Inflamação/metabolismo , Insulina/sangue , Interleucina-1beta/efeitos dos fármacos , Interleucina-1beta/metabolismo , Memória/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
6.
Breast Cancer Res Treat ; 174(2): 469-477, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30515680

RESUMO

INTRODUCTION: Breast cancer (BC) is the leading cause of cancer death in Caribbean women. Across the Caribbean islands, the prevalence of hereditary breast cancer among unselected breast cancer patients ranges from 5 to 25%. Moreover, the prevalence of BC among younger women and the high mortality in the Caribbean region are notable. This BC burden presents an opportunity for cancer prevention and control that begins with genetic testing among high-risk women. Measured response to positive genetic test results includes the number of preventive procedures and cascade testing in family members. We previously reported data on an active approach to promote cascade testing in the Bahamas and report on preventive procedures showing moderate uptake. Here, we describe a clinically structured and community-partnered approach to the dissemination and follow-up of genetic test results including family counseling for the promotion of risk mitigation strategies and cascade testing in our Trinidadian cohort of patients tested positive for BC predisposition genes. METHODS: As a part of our initial study of BC genetic testing in Trinidad and Tobago, all participants received pre-test counseling including three-generation pedigree and genetic testing for BRCA1/2, PALB2, and RAD51C. The study was approved by the University of Miami IRB and the Ethics Committee of the Ministry of Health, Trinidad and Tobago. We prospectively evaluated a clinically structured approach to genetic counseling and follow-up of BC mutation carriers in Trinidad and Tobago in 2015. The intervention consisted of (1) engaging twenty-nine BC patients with a deleterious gene mutation (probands), and (2) invitation of their at-risk relatives to attend to a family counseling session. The session included information on the meaning of their results, risk of inheritance, risk of cancer, risk-reduction options, offering of cascade testing to family members, and follow-up of proband decision-making over two years. RESULTS: Twenty-four of twenty-nine mutation carriers (82.8%) consented to enroll in the study. At initial pedigree review, we identified 125 at-risk relatives (ARR). Seventy-seven ARR (62%) attended the family counseling sessions; of these, 76 ARR (99%) consented to be tested for their family gene mutation. Genetic sequencing revealed that of the 76 tested, 35 (46%) ARR were carriers of their family mutation. The ARR received their results and were urged to take preventative measures at post-test counseling. At 2-year follow-up, 6 of 21 probands with intact breasts elected to pursue preventive mastectomy (28.5%) and 4 of 20 women with intact ovaries underwent RRSO (20%). CONCLUSIONS: In Trinidad and Tobago, a clinically structured and partnered approach to our testing program led to a significant rate of proband response by completing the intervention counseling session, executing risk-reducing procedures as well as informing and motivating at-risk relatives, thereby demonstrating the utility and efficacy of this BC control program.


Assuntos
Neoplasias da Mama/genética , Aconselhamento Genético/métodos , Testes Genéticos/métodos , Mutação em Linhagem Germinativa , Análise de Sequência de DNA/métodos , Adulto , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/diagnóstico , Proteínas de Ligação a DNA/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Pessoa de Meia-Idade , Linhagem , Mastectomia Profilática/estatística & dados numéricos , Estudos Prospectivos , Trinidad e Tobago/epidemiologia , Adulto Jovem
7.
Clin Genet ; 96(5): 461-467, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31368132

RESUMO

Von Hippel-Lindau disease (VHL) is a heritable condition caused by pathogenic variants in VHL and is characterized by benign and malignant lesions in the central nervous system (CNS) and abdominal viscera. Due to its variable expressivity, existing efforts to collate VHL patient data do not adequately capture all VHL manifestations. We developed a comprehensive and standardized VHL database in the web-based application, REDCap, that thoroughly captures all VHL manifestation data. As an initial trial, information from 86 VHL patients from the University Health Network/Hospital for Sick Children was populated into the database. Analysis of this cohort showed missense variants occurring with the greatest frequency, with all variants localizing to the α- or ß-domains of VHL. The most prevalent manifestations were central nervous system (CNS), renal, and retinal neoplasms, which were associated with frameshift variants and large deletions. We observed greater age-related penetrance for CNS hemangioblastomas with truncating variants compared to missense, while the reverse was true for pheochromocytomas. We demonstrate the utility of a comprehensive VHL database, which supports the standardized collection of clinical and genetic data specific to this patient population. Importantly, we expect that its web-based design will facilitate broader international collaboration and lead to a better understanding of VHL.


Assuntos
Hemangioblastoma/genética , Feocromocitoma/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Doença de von Hippel-Lindau/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Feminino , Hemangioblastoma/epidemiologia , Hemangioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/genética , Linhagem , Penetrância , Feocromocitoma/epidemiologia , Feocromocitoma/patologia , Adulto Jovem , Doença de von Hippel-Lindau/epidemiologia , Doença de von Hippel-Lindau/patologia
8.
Org Biomol Chem ; 17(7): 1970-1978, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30362485

RESUMO

Thioformamides are easily prepared - under full chemocontrol - through the partial reduction of isothiocyanates with the in situ generated Schwartz reagent. The high electrophilicity of the starting materials enables the straightforward addition of the hydride ion, thus constituting a reliable and high-yielding method for obtaining variously functionalized thioformamides. Sensitive chemical groups to the reduction conditions such as nitro, ester, alkene, azo, azide and keto groups do not interfere with the chemoselectivity of the process. Moreover, the stereochemical information embodied in the starting material is fully retained in the final products. The synthetic potential of the selected thioformamide template is also briefly discussed.

9.
J Clin Densitom ; 22(1): 125-149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-28739080

RESUMO

Members of the College of Physicians and Surgeons of Ontario Endocrinology and Metabolism Peer Review Network have been involved in a quality improvement project to help standardize the peer assessment of physicians practicing in endocrinology and metabolism. This has included developing state-of-the-art summaries of common endocrine problems by Canadian experts in endocrinology and metabolism. These tools have been developed in response to the educational needs, as identified by peer reviewers, of practicing endocrinologists in Ontario. These pedagogical tools aim not only to standardize the documentation of the clinical performance of endocrinologists but also to make the process more transparent and to improve the quality of patient care in Ontario. This article summarizes the project and also provides the tools developed for the endocrinology and metabolism section of the College of Physicians and Surgeons of Ontario.


Assuntos
Cuidados Críticos/normas , Doenças do Sistema Endócrino , Endocrinologia/métodos , Doenças Metabólicas , Revisão por Pares/normas , Melhoria de Qualidade , Diagnóstico Diferencial , Doenças do Sistema Endócrino/diagnóstico , Doenças do Sistema Endócrino/terapia , Endocrinologia/normas , Humanos , Doenças Metabólicas/diagnóstico , Doenças Metabólicas/terapia
10.
J Am Chem Soc ; 140(50): 17632-17642, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30495946

RESUMO

The regio- and stereoselective addition of germanium and zinc across the C-C triple bond of nitrogen-, sulfur-, oxygen-, and phosphorus-substituted terminal and internal alkynes is achieved by reaction with a combination of R3GeH and Et2Zn. Diagnostic experiments support a radical-chain mechanism and the ß-zincated vinylgermanes that show exceptional stability are characterized by NMR spectroscopy and X-ray crystallography. The unique feature of this new radical germylzincation reaction is that the C(sp2)-Zn bond formed remains available for subsequent in situ Cu(I)- or Pd(0)-mediated C-C or C-heteroatom bond formation with retention of the double bond geometry. These protocols offer modular access to elaborated tri- and tetrasubstituted vinylgermanes decorated with heteroatom substituents ß to germanium that are useful for the preparation of stereodefined alkenes.

11.
Synapse ; 72(8): e22036, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29740871

RESUMO

Aging is a stage of life where cognitive and motor functions are impaired. This is because oxidative and inflammatory processes exacerbate neurodegeneration, which affects dendritic morphology and neuronal communication of limbic regions with memory loss. Recently, the use of trophic substances has been proposed to prevent neuronal deterioration. The neuropeptide-12 (N-PEP-12) has been evaluated in elderly patients with dementia, showing improvements in cognitive tasks due to acts as a neurotrophic factor. In the present work, we evaluated the effect of N-PEP-12 on motor activity and recognition memory, as well as its effects on dendritic morphology and the immunoreactivity of GFAP, Synaptophysin (SYP), and BDNF in neurons of the prefrontal cortex (PFC), dorsal hippocampus (DH) and nucleus accumbens (NAcc) of aged rats. The results show that N-PEP-12 improved the recognition memory, but the motor activity was not modified compared to the control animals. N-PEP-12 increases the density of dendritic spines and the total dendritic length in neurons of the PFC (layers 3 and 5) and in DH (CA1 and CA3). Interestingly NAcc neurons showed a reduction in the number of dendritic spines. In the N-PEP-12 animals, when evaluating the immunoreactivity for SYP and BDNF, there was an increase in the three brain regions, while the mark for GFAP decreased significantly. Our results suggest that N-PEP-12 promotes neuronal plasticity in the limbic system of aged animals, which contributes to improving recognition memory. In this sense, N-PEP-12 can be considered as a pharmacological alternative to prevent or delay brain aging and control senile dementias.


Assuntos
Envelhecimento/efeitos dos fármacos , Aminoácidos/farmacologia , Sistema Límbico/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Nootrópicos/farmacologia , Reconhecimento Psicológico/efeitos dos fármacos , Envelhecimento/metabolismo , Envelhecimento/patologia , Envelhecimento/psicologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Dendritos/efeitos dos fármacos , Dendritos/metabolismo , Dendritos/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Sistema Límbico/metabolismo , Sistema Límbico/patologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Plasticidade Neuronal/fisiologia , Ratos Sprague-Dawley , Reconhecimento Psicológico/fisiologia , Sinaptofisina/metabolismo
12.
Mod Pathol ; 29(2): 131-42, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26743473

RESUMO

Originally classified as a variant of silent corticotroph adenoma, silent subtype 3 adenomas are a distinct histologic variant of pituitary adenoma of unknown cytogenesis. We reviewed the clinical, biochemical, radiological, immunohistochemical and ultrastructural features of 31 silent subtype 3 adenomas to clarify their cellular origin. Among 25 with clinical and/or radiological data, all were macroadenomas; there was cavernous sinus invasion in 30% of cases and involvement of the clivus in 17% of cases. Almost 90% of patients were symptomatic; 67% had mass effect symptoms, 37% were hypogonadal and 8% had secondary adrenal insufficiency. Significant hormonal excess in 29% of cases included hyperthyroidism in 17%, acromegaly in 8% and hyperprolactinemia above 150 µg/l in 4%. Two individuals with hyperprolactinemia who were younger than 30 years had multiple endocrine neoplasia type 1. Immunohistochemically, all 31 tumors were diffusely positive for the pituitary lineage-specific transcription factor Pit-1. Although three only expressed Pit-1, others revealed variable positivity for one or more hormones of Pit-1 cell lineage (growth hormone, prolactin, thyroid-stimulating hormone), as well as alpha-subunit and estrogen receptor. Most tumors exhibited perinuclear reactivity for keratins with the CAM5.2 antibody; scattered fibrous bodies were noted in five (16%) tumors. The mean MIB-1 labeling index was 4% (range, 1-9%). Fourteen cases examined by electron microscopy were composed of a monomorphous population of large polygonal or elongated cells with nuclear spheridia. Sixty-five percent of patients had residual disease after surgery; after a mean follow-up of 48.4 months (median 41.5; range=2-171) disease progression was documented in 53% of those cases. These data identify silent subtype 3 adenomas as aggressive monomorphous plurihormonal adenomas of Pit-1 lineage that may be associated with hyperthyroidism, acromegaly or galactorrhea and amenorrhea. Our findings argue against the use of the nomenclature 'silent' for these tumors. To better reflect the characteristics of these tumors, we propose that they be classified as 'poorly differentiated Pit-1 lineage adenomas'.


Assuntos
Adenoma/química , Biomarcadores Tumorais/análise , Diferenciação Celular , Linhagem da Célula , Neoplasias Hipofisárias/química , Fator de Transcrição Pit-1/análise , Acromegalia/etiologia , Adenoma/classificação , Adenoma/complicações , Adenoma/cirurgia , Adenoma/ultraestrutura , Adolescente , Adulto , Idoso , Amenorreia/etiologia , Feminino , Galactorreia/etiologia , Humanos , Hipertireoidismo/etiologia , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasia Residual , Neoplasias Hipofisárias/classificação , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/ultraestrutura , Valor Preditivo dos Testes , Estudos Retrospectivos , Terminologia como Assunto , Resultado do Tratamento , Adulto Jovem
13.
Org Biomol Chem ; 14(33): 7848-54, 2016 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-27461156

RESUMO

The addition of carbon (Grignard and organolithium reagents) and hydride nucleophiles (Schwartz reagent) to isocyanates and isothiocyanates constitutes a versatile, direct and high yielding approach to the synthesis of functionalized (thio)amide derivatives including haloamides and formamides. The chemoselective delivery of a nucleophilic (eventually configurationally stable) organometallic species to a given iso(thio)cyanate is the crucial parameter for the success of the strategy. Thus, the influence of the factors governing classical methodologies (e.g. dehydrative condensation) such as steric hindrance and electronic properties of the reactants become practically negligible.

14.
Postgrad Med J ; 91(1076): 331-42, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26045561

RESUMO

Endogenous Cushing's syndrome is a rare endocrine disorder that incurs significant cardiovascular morbidity and mortality, due to glucocorticoid excess. It comprises adrenal (20%) and non-adrenal (80%) aetiologies. While the majority of cases are attributed to pituitary or ectopic corticotropin (ACTH) overproduction, primary cortisol-producing adrenal cortical lesions are increasingly recognised in the pathophysiology of Cushing's syndrome. Our understanding of this disease has progressed substantially over the past decade. Recently, important mechanisms underlying the pathogenesis of adrenal hypercortisolism have been elucidated with the discovery of mutations in cyclic AMP signalling (PRKACA, PRKAR1A, GNAS, PDE11A, PDE8B), armadillo repeat containing 5 gene (ARMC5) a putative tumour suppressor gene, aberrant G-protein-coupled receptors, and intra-adrenal secretion of ACTH. Accurate subtyping of Cushing's syndrome is crucial for treatment decision-making and requires a complete integration of clinical, biochemical, imaging and pathology findings. Pathological correlates in the adrenal glands include hyperplasia, adenoma and carcinoma. While the most common presentation is diffuse adrenocortical hyperplasia secondary to excess ACTH production, this entity is usually treated with pituitary or ectopic tumour resection. Therefore, when confronted with adrenalectomy specimens in the setting of Cushing's syndrome, surgical pathologists are most commonly exposed to adrenocortical adenomas, carcinomas and primary macronodular or micronodular hyperplasia. This review provides an update on the rapidly evolving knowledge of adrenal Cushing's syndrome and discusses the clinicopathological correlations of this important disease.

15.
Am J Med Genet A ; 164A(9): 2335-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24891185

RESUMO

We report on a 6-year-old child with a de novo 1.6 Mb deletion in the 3q26.31q26.32 region identified by SNP array, involving only one relevant gene: TBL1XR1. The girl shows non-specific, mild to moderate intellectual deficiency but no autistic behavior. Point mutations in TBL1XR1 have recently been implicated in three patients with intellectual disability (ID) and autistic features. Our report supports that haploinsufficiency for TBL1XR1 could be implicated in non-ASD autosomal dominant ID.


Assuntos
Deficiências do Desenvolvimento/genética , Deleção de Genes , Deficiência Intelectual/genética , Proteínas Nucleares/genética , Receptores Citoplasmáticos e Nucleares/genética , Proteínas Repressoras/genética , Criança , Pré-Escolar , Fácies , Feminino , Humanos , Recém-Nascido , Polimorfismo de Nucleotídeo Único/genética , Gravidez
16.
Am J Respir Crit Care Med ; 188(2): 240-8, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23328524

RESUMO

RATIONALE: Obstructive sleep apnea is a risk factor for dyslipidemia and atherosclerosis, which have been attributed to chronic intermittent hypoxia (CIH). Intermittent hypoxia inhibits a key enzyme of lipoprotein clearance, lipoprotein lipase, and up-regulates a lipoprotein lipase inhibitor, angiopoietin-like 4 (Angptl4), in adipose tissue. The effects and mechanisms of Angptl4 up-regulation in sleep apnea are unknown. OBJECTIVES: To examine whether CIH induces dyslipidemia and atherosclerosis by increasing adipose Angptl4 via hypoxia-inducible factor-1 (HIF-1). METHODS: ApoE(-/-) mice were exposed to intermittent hypoxia or air for 4 weeks while being treated with Angptl4-neutralizing antibody or vehicle. MEASUREMENTS AND MAIN RESULTS: In vehicle-treated mice, hypoxia increased adipose Angptl4 levels, inhibited adipose lipoprotein lipase, increased fasting levels of plasma triglycerides and very low density lipoprotein cholesterol, and increased the size of atherosclerotic plaques. The effects of CIH were abolished by the antibody. Hypoxia-induced increases in plasma fasting triglycerides and adipose Angptl4 were not observed in mice with germline heterozygosity for a HIF-1α knockout allele. Transgenic overexpression of HIF-1α in adipose tissue led to dyslipidemia and increased levels of adipose Angptl4. In cultured adipocytes, constitutive expression of HIF-1α increased Angptl4 levels, which was abolished by siRNA. Finally, in obese patients undergoing bariatric surgery, the severity of nocturnal hypoxemia predicted Angptl4 levels in subcutaneous adipose tissue. CONCLUSIONS: HIF-1-mediated increase in adipose Angptl4 and the ensuing lipoprotein lipase inactivation may contribute to atherosclerosis in patients with sleep apnea.


Assuntos
Angiopoietinas/metabolismo , Aterosclerose/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Gordura Subcutânea/fisiopatologia , Adipócitos/metabolismo , Adulto , Idoso , Proteína 4 Semelhante a Angiopoietina , Animais , Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Feminino , Humanos , Hipóxia/metabolismo , Lipase Lipoproteica/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos SENCAR , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Apneia Obstrutiva do Sono/metabolismo , Gordura Subcutânea/metabolismo , Regulação para Cima/fisiologia
17.
Rev Alerg Mex ; 71(1): 69, 2024 Feb 01.
Artigo em Espanhol | MEDLINE | ID: mdl-38683086

RESUMO

OBJECTIVE: To compare the relative frequencies of immune cell populations in the peripheral blood according to A. lumbricoides infection status. METHODS: Peripheral blood samples were collected from participants infected (n = 35) and uninfected with A. lumbricoides (n=27) residing in different rural municipalities of Bolívar. Infection was diagnosed using two coprological examinations and the Kato-Katz technique. Immunophenotyping was performed using two panels of markers and staining in fresh blood. The flow cytometry reading was performed on a spectral cytometer (Northern Lights, Cytek, USA). The populations identified in the first panel (Figure 1) were T lymphocytes (CD45+ CD3+), CD4+ or CD8+, B lymphocytes (CD45+ SSClow CD3- CD19+), neutrophils (CD45+ SSChi CD3- CD16+), and eosinophils (CD45+ SSChi CD3- CD16low). Monocytes were identified in another panel (Figure 2): classical (CD14++ CD16 -), intermediate (CD14++ CD16+), and non-classical (CD14+ CD16++). Dendritic cells, including CD123 + + CD303 + (plasmacytoid), HLA-DR + + CD1c + (myeloid CD1c +), and CD14-CD141 + + (myeloid CD141 +), were also identified. The study received approval from the Ethics Committee of the University of Cartagena, and participants provided informed consent. Funding was provided by the Colombian Sistema General de Regalías under BPIN2020000100405 - BPIN2020000100364. RESULTS: No significant differences were observed in age [mean cases: 35.69 (SD: 17.7) vs. controls: 37.04 (SD: 15.6) years] or sex (cases: 62.9% vs. controls: 74.1%) (Table 1). All infections were mild, with a median of 96 eggs (IQR, 48-216). A marginally significant difference was observed only in the percentage of neutrophils (45.37% in cases vs. 54.79% in controls, p=0.041) (Figure 3). Although the frequency of eosinophils was higher in the cases (8.1% vs. 6%), this difference was not significant (p=0.138) (Figure 3). No significant differences were observed in the populations of monocytes or dendritic cells between cases and controls (Figure 4). CONCLUSION: Mild A. lumbricoides infection appears to affect the number of neutrophils in peripheral blood. The low infection intensity in the studied samples may explain the lack of a significant impact on other cellular populations.


OBJETIVO: Comparar las frecuencias relativas de poblaciones de células inmunes en sangre periférica de acuerdo con el estado de infección por A. lumbricoides. MÉTODOS: Se recolectaron muestras de sangre periférica de participantes infectados (n=35) y no infectados con A. lumbricoides (n=27), residentes en distintos municipios rurales de Bolívar. La infección se diagnosticó por dos métodos coprológicos y la técnica de Kato-Katz. El inmunofenotipo se determinó con dos baterías de marcadores y tinciones en sangre fresca. La lectura fue realizada en un citómetro espectral (Northern Lights, Cytek, USA). Las poblaciones identificadas en la primera batería (Figura 1) fueron linfocitos T (CD45+ CD3+) CD4+ o CD8+, linfocitos B (CD45+ SSClow CD3- CD19+), neutrófilos (CD45+ SSChi CD3- CD16+), y eosinófilos (CD45+ SSChi CD3- CD16low). Los monocitos se identificaron en otra batería (Figura 2): clásicos (CD14++ CD16­), intermedios (CD14++ CD16+), y no clásicos (CD14+ CD16++). También se identificaron células dendríticas, tales como: CD123++ CD303+ (plasmocitoides), HLA-DR++ CD1c+ (mieloides CD1c+), y CD14- CD141++ (mieloides CD141+). El estudio recibió la aprobación del Comité de Ética de la Universidad de Cartagena, y los participantes otorgaron su consentimiento informado. La financiación fue proporcionada por el Sistema General de Regalías de Colombia, bajo el BPIN2020000100405 - BPIN2020000100364. RESULTADOS: No se observaron diferencias significativas en edad [media = casos: 35,69 (DE: 17,7) vs controles: 37,04 (DE: 15,6 años] o sexo (casos: 62,9% vs. controles: 74,1%). Todas las infecciones fueron leves con una mediana de huevos de 96 (RIC: 48 - 216). Solo se encontró diferencia significativa marginal en el porcentaje de neutrófilos (45,37% en los casos vs 54,79% en controles, p=0,041). Si bien la frecuencia de eosinófilos fue más alta en los casos (8,1% vs. 6%), esta diferencia no alcanzó la significancia (p=0,138). No se observaron diferencias significativas en las poblaciones de monocitos o células dendríticas entre casos y controles (Figura 4). CONCLUSIÓN: La infección leve por A. lumbricoides parece afectar el número de neutrófilos en sangre periférica. Es posible que por la baja intensidad de la infección en la muestra estudiada, no se detecte un impacto importante de la misma sobre el resto de las poblaciones celulares. Palabras claves: Helmintos; Ascaris lumbricoides; Citometría de flujo; Inmunofenotipado; Neutrófilos.


Assuntos
Ascaríase , Humanos , Masculino , Feminino , Ascaríase/imunologia , Ascaríase/epidemiologia , Adulto , Adolescente , Animais , Adulto Jovem , Saúde da População Rural , Criança , Ascaris lumbricoides , Pessoa de Meia-Idade , Colômbia
18.
Chem Sci ; 15(23): 8841-8849, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38873069

RESUMO

Cucurbit[n]urils, renowned for their host-guest chemistry, are becoming versatile biomimetic receptors. Herein, we report that cucurbit[7]uril (CB[7]) accelerates the intramolecular Diels-Alder (IMDA) reaction for previously elusive and unreactive tertiary N-methyl-N-(homo)allyl-2-furfurylamines by up to 4 orders of magnitude under mild conditions. Using 1H NMR titrations and ITC experiments, we characterize the dissimilar thermodynamic and kinetic properties of the complexes. We also determine the activation parameters (ΔG ≠, ΔH ≠ and ΔS ≠) leading to the transition state of the IMDA reactions, both in the bulk and included in CB[7], to shed light on the key role of the receptor on the acceleration observed. CB[7] acts as an "entropy trap" utilizing guest binding to primarily pay the entropy penalty for reorganizing the substrate in a high-energy reactive conformation that resembles the geometry of the highly ordered transition state required for the IMDA reaction. This study underscores the potential of cucurbit[n]urils as artificial active sites, emulating specific aspects of enzymatic catalysis.

19.
J Lipid Res ; 54(4): 1058-65, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23386706

RESUMO

Chronic intermittent hypoxia (CIH) inhibits plasma lipoprotein clearance and adipose lipoprotein lipase (LPL) activity in association with upregulation of an LPL inhibitor angiopoietin-like protein 4 (Angptl4). We hypothesize that CIH inhibits triglyceride (TG) uptake via Angptl4 and that an anti-Angptl4-neutralizing antibody would abolish the effects of CIH. Male C57BL/6J mice were exposed to four weeks of CIH or intermittent air (IA) while treated with Ab (30 mg/kg ip once a week). TG clearance was assessed by [H(3)]triolein administration retroorbitally. CIH delayed TG clearance and suppressed TG uptake and LPL activity in all white adipose tissue depots, brown adipose tissue, and lungs, whereas heart, liver, and spleen were not affected. CD146+ CD11b- pulmonary microvascular endothelial cells were responsible for TG uptake in the lungs and its inhibition by CIH. Antibody to Angptl4 decreased plasma TG levels and increased TG clearance and uptake into adipose tissue and lungs in both control and CIH mice to a similar extent, but did not reverse the effects of CIH. The antibody reversed the effects of CIH on LPL in adipose tissue and lungs. In conclusion, CIH inactivates LPL by upregulating Angptl4, but inhibition of TG uptake occurs predominantly via an Angptl4/LPL-independent mechanism.


Assuntos
Hipóxia/fisiopatologia , Triglicerídeos/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Proteína 4 Semelhante a Angiopoietina , Angiopoietinas/genética , Angiopoietinas/metabolismo , Animais , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Lipoproteínas/genética , Lipoproteínas/metabolismo , Pulmão , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
Am J Sports Med ; 51(7): 1859-1871, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37092707

RESUMO

BACKGROUND: As blood flow restriction (BFR) utilization continues to rise, it is crucial to define optimal parameters for use. Currently unknown are the effects of occlusion level during BFR on muscle activity in the proximal shoulder. PURPOSE/HYPOTHESIS: The purpose of this study was to compare electromyographic amplitude (EMGa) of shoulder musculature during exercise using limb occlusion percentages (LOPs). The authors hypothesized that EMGa would increase concurrently with occlusion. STUDY DESIGN: Controlled laboratory study. METHODS: α Fifteen healthy adults were recruited and underwent 4 experimental sessions, performing 3 common rotator cuff exercises at low intensity (20% maximal strength) to failure in the following order: cable external rotation (ER), cable internal rotation (IR), and dumbbell scaption. Exercises were completed at a different occlusion pressure (0%, 25%, 50%, and 75% LOP- order randomized) applied at the proximal arm. EMGa was recorded from shoulder musculature proximal to the occlusion site and averaged across 5-repetition intervals and overall for the first 30 repetitions. An analysis of variance repeated on occlusion pressure followed by a Bonferroni post hoc test was used to compare EMGa, repetitions to fatigue, and ratings of discomfort (visual analog scale [VAS], 0-10) between occlusion pressures. The type 1 error was set at α = .05 for all analyses. RESULTS: Significant effects of the occlusion level on shoulder muscle EMGa were observed for all exercises (P < .05) with diminishing returns above 50% LOP (overall). For ER, elevations in EMGa were observed at ≥50% LOP for the anterior deltoid, middle deltoid, infraspinatus, and trapezius compared with 0% LOP (P < .05). For IR, elevations in EMGa were observed at ≥25% LOP for the anterior deltoid and trapezius compared with 0% LOP (P < .05). For the teres minor, a significant elevation in EMGa occurred at 75% LOP compared with 0%, 25%, and 50% LOP (P < .05). A decrease in EMGa was observed at ≥50% LOP compared with 0% LOP for the posterior deltoid (P < .05). For scaption, an increase in EMGa was observed at ≥25% LOP for the infraspinatus and teres minor muscles, at 75% LOP for the posterior deltoid, and at ≥50% LOP for the trapezius compared with 0% LOP (P < .05). Decreases in repetitions to failure relative to 0% LOP were observed at 75% LOP for ER (0%: 47 ± 5; 75%: 40 ± 2; P = .034), IR (0%: 82 ± 10; 75%: 64 ± 5; P = .017), and scaption (0%: 85 ± 9; 75%: 64 ± 6; P < .001). A significant linear increase in discomfort was observed for all exercises with increasing occlusion pressures (VAS: 0-10, 0% → 75% LOP; ER: 2.2 ± 0.4 → 7.2 ± 0.3; IR: 1.3 ± 0.2 → 6.1 ± 0.6; scaption: 1.3 ± 0.4 → 6.1 ± 0.4; P < .01). CONCLUSION: There are several differences in muscle activation about the shoulder based on exercise and occlusion when utilizing BFR. Increasing the percentage of limb occlusion leads to heightened EMGa with diminished returns past 50% LOP when considering muscle activation, discomfort, and achievable exercise volume. CLINICAL RELEVANCE: These findings may be used to refine upper extremity BFR guidelines.


Assuntos
Articulação do Ombro , Ombro , Adulto , Humanos , Ombro/fisiologia , Eletromiografia , Músculo Esquelético/fisiologia , Manguito Rotador/fisiologia
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