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1.
Nat Immunol ; 23(10): 1495-1506, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36151395

RESUMO

The immune system can eliminate tumors, but checkpoints enable immune escape. Here, we identify immune evasion mechanisms using genome-scale in vivo CRISPR screens across cancer models treated with immune checkpoint blockade (ICB). We identify immune evasion genes and important immune inhibitory checkpoints conserved across cancers, including the non-classical major histocompatibility complex class I (MHC class I) molecule Qa-1b/HLA-E. Surprisingly, loss of tumor interferon-γ (IFNγ) signaling sensitizes many models to immunity. The immune inhibitory effects of tumor IFN sensing are mediated through two mechanisms. First, tumor upregulation of classical MHC class I inhibits natural killer cells. Second, IFN-induced expression of Qa-1b inhibits CD8+ T cells via the NKG2A/CD94 receptor, which is induced by ICB. Finally, we show that strong IFN signatures are associated with poor response to ICB in individuals with renal cell carcinoma or melanoma. This study reveals that IFN-mediated upregulation of classical and non-classical MHC class I inhibitory checkpoints can facilitate immune escape.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Inibidores de Checkpoint Imunológico , Evasão da Resposta Imune , Interferon gama/genética , Interferon gama/metabolismo , Subfamília C de Receptores Semelhantes a Lectina de Células NK
2.
Cell ; 173(1): 117-129.e14, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29570992

RESUMO

Angiogenesis, the formation of new blood vessels by endothelial cells (ECs), is an adaptive response to oxygen/nutrient deprivation orchestrated by vascular endothelial growth factor (VEGF) upon ischemia or exercise. Hypoxia is the best-understood trigger of VEGF expression via the transcription factor HIF1α. Nutrient deprivation is inseparable from hypoxia during ischemia, yet its role in angiogenesis is poorly characterized. Here, we identified sulfur amino acid restriction as a proangiogenic trigger, promoting increased VEGF expression, migration and sprouting in ECs in vitro, and increased capillary density in mouse skeletal muscle in vivo via the GCN2/ATF4 amino acid starvation response pathway independent of hypoxia or HIF1α. We also identified a requirement for cystathionine-γ-lyase in VEGF-dependent angiogenesis via increased hydrogen sulfide (H2S) production. H2S mediated its proangiogenic effects in part by inhibiting mitochondrial electron transport and oxidative phosphorylation, resulting in increased glucose uptake and glycolytic ATP production.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Aminoácidos Sulfúricos/deficiência , Sulfeto de Hidrogênio/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator 4 Ativador da Transcrição/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Aminoácidos Sulfúricos/metabolismo , Animais , Cistationina gama-Liase/metabolismo , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isquemia/metabolismo , Isquemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica , Condicionamento Físico Animal , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética
3.
Immunity ; 53(6): 1131-1132, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33326763

RESUMO

Tumors use active immunosuppressive mechanisms to evade immune recognition and shape the local inflammatory environment. In this issue of Immunity, Bonavita et al. report that tumor-derived PGE2 blocks early activation of natural killer cells and interferes with subsequent adaptive immune cell recruitment to the tumor.


Assuntos
Dinoprostona , Neoplasias , Cefaleia , Humanos , Inibidores de Checkpoint Imunológico , Células Matadoras Naturais , Fenótipo
4.
Nature ; 622(7984): 850-862, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37794185

RESUMO

Immune checkpoint blockade is effective for some patients with cancer, but most are refractory to current immunotherapies and new approaches are needed to overcome resistance1,2. The protein tyrosine phosphatases PTPN2 and PTPN1 are central regulators of inflammation, and their genetic deletion in either tumour cells or immune cells promotes anti-tumour immunity3-6. However, phosphatases are challenging drug targets; in particular, the active site has been considered undruggable. Here we present the discovery and characterization of ABBV-CLS-484 (AC484), a first-in-class, orally bioavailable, potent PTPN2 and PTPN1 active-site inhibitor. AC484 treatment in vitro amplifies the response to interferon and promotes the activation and function of several immune cell subsets. In mouse models of cancer resistant to PD-1 blockade, AC484 monotherapy generates potent anti-tumour immunity. We show that AC484 inflames the tumour microenvironment and promotes natural killer cell and CD8+ T cell function by enhancing JAK-STAT signalling and reducing T cell dysfunction. Inhibitors of PTPN2 and PTPN1 offer a promising new strategy for cancer immunotherapy and are currently being evaluated in patients with advanced solid tumours (ClinicalTrials.gov identifier NCT04777994 ). More broadly, our study shows that small-molecule inhibitors of key intracellular immune regulators can achieve efficacy comparable to or exceeding that of antibody-based immune checkpoint blockade in preclinical models. Finally, to our knowledge, AC484 represents the first active-site phosphatase inhibitor to enter clinical evaluation for cancer immunotherapy and may pave the way for additional therapeutics that target this important class of enzymes.


Assuntos
Imunoterapia , Neoplasias , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteína Tirosina Fosfatase não Receptora Tipo 2 , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos , Inibidores de Checkpoint Imunológico , Imunoterapia/métodos , Interferons/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 2/antagonistas & inibidores , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
5.
Nature ; 593(7860): 580-585, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33981039

RESUMO

Adaptive thermogenesis has attracted much attention because of its ability to increase systemic energy expenditure and to counter obesity and diabetes1-3. Recent data have indicated that thermogenic fat cells use creatine to stimulate futile substrate cycling, dissipating chemical energy as heat4,5. This model was based on the super-stoichiometric relationship between the amount of creatine added to mitochondria and the quantity of oxygen consumed. Here we provide direct evidence for the molecular basis of this futile creatine cycling activity in mice. Thermogenic fat cells have robust phosphocreatine phosphatase activity, which is attributed to tissue-nonspecific alkaline phosphatase (TNAP). TNAP hydrolyses phosphocreatine to initiate a futile cycle of creatine dephosphorylation and phosphorylation. Unlike in other cells, TNAP in thermogenic fat cells is localized to the mitochondria, where futile creatine cycling occurs. TNAP expression is powerfully induced when mice are exposed to cold conditions, and its inhibition in isolated mitochondria leads to a loss of futile creatine cycling. In addition, genetic ablation of TNAP in adipocytes reduces whole-body energy expenditure and leads to rapid-onset obesity in mice, with no change in movement or feeding behaviour. These data illustrate the critical role of TNAP as a phosphocreatine phosphatase in the futile creatine cycle.


Assuntos
Fosfatase Alcalina/metabolismo , Mitocôndrias/enzimologia , Fosfocreatina/metabolismo , Termogênese , Adipócitos/metabolismo , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/metabolismo , Animais , Temperatura Baixa , Metabolismo Energético , Hidrólise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/metabolismo , Obesidade/metabolismo
6.
Nature ; 595(7866): 309-314, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33953401

RESUMO

Epigenetic dysregulation is a defining feature of tumorigenesis that is implicated in immune escape1,2. Here, to identify factors that modulate the immune sensitivity of cancer cells, we performed in vivo CRISPR-Cas9 screens targeting 936 chromatin regulators in mouse tumour models treated with immune checkpoint blockade. We identified the H3K9 methyltransferase SETDB1 and other members of the HUSH and KAP1 complexes as mediators of immune escape3-5. We also found that amplification of SETDB1 (1q21.3) in human tumours is associated with immune exclusion and resistance to immune checkpoint blockade. SETDB1 represses broad domains, primarily within the open genome compartment. These domains are enriched for transposable elements (TEs) and immune clusters associated with segmental duplication events, a central mechanism of genome evolution6. SETDB1 loss derepresses latent TE-derived regulatory elements, immunostimulatory genes, and TE-encoded retroviral antigens in these regions, and triggers TE-specific cytotoxic T cell responses in vivo. Our study establishes SETDB1 as an epigenetic checkpoint that suppresses tumour-intrinsic immunogenicity, and thus represents a candidate target for immunotherapy.


Assuntos
Inativação Gênica , Histona-Lisina N-Metiltransferase/metabolismo , Neoplasias/genética , Neoplasias/imunologia , Animais , Antígenos Virais/imunologia , Sistemas CRISPR-Cas/genética , Cromatina/genética , Cromatina/metabolismo , Elementos de DNA Transponíveis/genética , Modelos Animais de Doenças , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia
7.
Immunity ; 45(3): 461-463, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27653596

RESUMO

Obesity shifts the immune phenotype from M2 macrophage polarization to M1, which causes metabolic dysfunction. In this issue of Immunity, Kumamoto et al. (2016) identify a tissue-resident mononuclear phagocyte population that promotes weight gain and glucose intolerance but are defined by the M2 marker CD301b.


Assuntos
Lectinas Tipo C/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Fagócitos/imunologia , Fagócitos/metabolismo , Animais , Biomarcadores/metabolismo , Intolerância à Glucose/imunologia , Humanos , Lectinas Tipo C/imunologia , Aumento de Peso/imunologia
8.
Vox Sang ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39134074

RESUMO

BACKGROUND AND OBJECTIVES: In Japan, apheresis donation of plasma is allowed to a maximum of 24 times a year, and plateletpheresis are counted as two plasmapheresis donations. Diversion of the initial blood flow is conducted for all donations, and additionally, blood remaining in apheresis machine circuit is lost. Here, we aimed to investigate on the health impact of frequent apheresis donations, as measured by the serum ferritin (sFer). MATERIALS AND METHODS: A total of 538 male apheresis donors and 538 age-matched whole blood (WB) donors, who gave informed consent to join the study, were enrolled. sFer were compared, according to age. Another group of 19 apheresis donors were followed during four consecutive donations. RESULTS: About half (48%) of repeat male apheresis donors had iron deficiency (sFer < 26 ng/mL), compared with lower rates (13.9%) among male WB donors. It was evident in all age groups, except for teenagers, possibly because of the lower number of donations. Follow-up of the 19 donors for 4 months revealed a progressive decrease in sFer. CONCLUSION: Blood remaining in the apheresis machine circuit and diversion of the initial blood flow have been implicated in iron deficiency for many years. Taking the present results, the manufacturer of apheresis equipment was requested to improve it to allow rinseback of the remaining blood, which was achieved only for plateletpheresis. Until further improvement, plasmapheresis frequency was reduced to 12 times a year. Additional measures, such as oral supplementation of iron, need to be considered.

9.
Vox Sang ; 119(9): 912-920, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38872445

RESUMO

BACKGROUND AND OBJECTIVES: A more restrictive blood donation criterion has been applied in Japan, with a maximum volume of whole blood (WB) donation of 400 mL, allowing twice a year for female donors and thrice a year for male donors. However, iron deficiency was as high as 20.5% among female donors prior to donation, increasing to 37.7% after blood donation. More than 20 years have passed since then, so we set out to investigate the present situation. MATERIALS AND METHODS: A total of 2659 (male/female: 1496/1163) donors of 400 mL WB who gave informed consent to join the study were enrolled. Serum ferritin (sFer) of first-time/reactivated (FT/RA) donors were compared with those of repeat donors, according to gender and age; those who returned for subsequent donations during the study period were also followed up. RESULTS: About one-third of FT/RA female donors had iron deficiency, possibly reflecting its high incidence among the general population. Interestingly, although sFer levels were low among pre-menopausal FT/RA female donors, these values were not much different in repeat donors, whereas significant differences were observed between FT/RA and repeat donors among post-menopausal females and in most age groups among males. As expected, donors with a normal initial sFer (≥26 ng/mL) recovered faster than those with a low initial sFer. CONCLUSION: Female donors, especially, have iron deficiency even before donation, and the rate increased compared to what was found previously. Measures to prevent iron deficiency of blood donors is required, and studies are going on in Japan.


Assuntos
Doadores de Sangue , Ferritinas , Humanos , Feminino , Masculino , Ferritinas/sangue , Adulto , Japão/epidemiologia , Pessoa de Meia-Idade , Deficiências de Ferro , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Idoso , População do Leste Asiático
10.
Artigo em Inglês | MEDLINE | ID: mdl-39265554

RESUMO

INTRODUCTION: Strategies for treatment of tonsil carcinoma are under active investigation. Limiting surgical and radiation treatment volumes to the primary tumor and ipsilateral neck in appropriately selected patients is one such approach. Here, we present our institutional experience with treatment through ipsilateral surgical or radiotherapeutic neck management. METHODS: We retrospectively reviewed our institutional database of patients with tonsil carcinoma treated from 2012 to 2020. Patients were included for analysis if they received definitive radiation therapy (RT), definitive surgery (S), or surgery with post-operative radiation therapy (S-PORT) and whose treatment volumes were limited to the primary tumor and involved/elective ipsilateral neck. Patients who received radiation and/or surgery to the contralateral neck (including those with bilateral nodal involvement), as well as patients with metastatic disease, were excluded. Clinical factors including T- and N-stage (AJCC 7th edition), and HPV status (by p16 and/or HPV DNA PCR) were recorded, as were pathologic factors (when applicable) including margin status, extracapsular extension (ECE), lymphovascular invasion (LVSI), and perineural invasion (PNI). Overall survival (OS), progression free survival (PFS), and locoregional control (LRC) at 2 years were estimated using the Kaplan-Meier method. RESULTS: In total, 71 patients were treated with unilateral neck approaches: S (n=49), RT (n=10), and S+PORT (n=12). Among these patients, 32, 36, and 3 had T1, T2, and T3 disease, respectively. N-stage was N0, N1, N2a, N2b, and N3 in 22, 20, 5, 23, and 1 patient(s), respectively. Concurrent chemotherapy was administered in 12 patients. From those with recorded risk factors, 86% were HPV-positive, 20% had LVSI, 7% had PNI, 13% had ECE, and 5% had positive margins. From a median follow-up of 27 months, local, regional, and distant failures occurred in 5, 6, and 5 patients, respectively. No contralateral neck failures were recorded. At 2 years, OS, PFS, and LRC were 92% (95% CI 85-99%), 85% (95% CI 75-95%), and 88% (95% CI 80-98%), respectively. CONCLUSIONS: In patients with early T-stage tonsil carcinoma, treatment of the primary tumor and ipsilateral neck is associated with acceptable OS, PFS, and LRC. In this population, the risk of contralateral neck failure is likely very low regardless of primary treatment modality. Additional prospective studies are needed to determine the impact of limiting treatment extent to the unilateral neck.

11.
J Strength Cond Res ; 38(9): e521-e528, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39178393

RESUMO

ABSTRACT: Dos Santos, VR, Antunes, M, dos Santos, L, Nascimento, MA, Pina, FLC, Carneiro, NH, Trindade, MCC, Venturini, D, Barbosa, DS, and Cyrino, ES. Effects of different resistance training frequencies on body composition, muscular strength, muscle quality, and metabolic biomarkers in sarcopenic older women. J Strength Cond Res 38(9): e521-e528, 2024-Resistance training (RT) can ameliorate outcomes related to sarcopenia by promoting beneficial changes in muscular strength, skeletal muscle mass (SMM), and muscle quality. This study compared the effects of 12 weeks of RT performed 2 and 3 sessions a week on body composition, muscular strength, muscle quality, and metabolic biomarkers in sarcopenic older women. Thirty-four sarcopenic older women (>60 years) were randomly assigned to perform a whole-body RT program, either 2 (G2X, n = 18) or 3 (G3X, n = 16) sessions a week during 12 weeks (8 exercises, single set of 10-15 repetitions). Body composition, muscular strength, muscle quality, and metabolic biomarkers were assessed before and after the intervention. Both groups increased (p < 0.05) 1 repetition maximum total muscular strength (G2X = +20.4% and G3X = +21.0%), SMM (G2X = +4.0% and G3X = +7.0%), and improved muscle quality (G2X = +16.7% and G3X = +13.6%), with no differences between groups (p > 0.05). No change over time was found for IGF-1 and testosterone (p > 0.05). Our results suggest that 12 weeks of RT performed at a lower weekly frequency is as effective as a higher frequency in improving muscular strength, SMM, and muscle quality in sarcopenic older women.


Assuntos
Biomarcadores , Composição Corporal , Força Muscular , Músculo Esquelético , Treinamento Resistido , Sarcopenia , Humanos , Feminino , Treinamento Resistido/métodos , Força Muscular/fisiologia , Idoso , Composição Corporal/fisiologia , Sarcopenia/fisiopatologia , Sarcopenia/metabolismo , Sarcopenia/terapia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Biomarcadores/análise , Pessoa de Meia-Idade
12.
J Org Chem ; 88(22): 15580-15588, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37933871

RESUMO

Benzofuran and naphthofuran derivatives are synthesized from readily available phenols and naphthols. Regioselective ring openings of 2H-azirine followed by in situ aromatization using a catalytic amount of Brønsted acid have established the novelty of the methodology. The involvement of a series of 2H-azirines with a variety of phenols, 1-naphthols, and 2-naphthols showed the generality of the protocol. In-depth density functional theory calculations revealed the reaction mechanism with the energies of the intermediates and transition states of a model reaction. An alternate pathway of the mechanism has also been proposed with computer modeling.

13.
J Org Chem ; 87(12): 7610-7617, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35171607

RESUMO

Ellipticine was synthesized in six steps and 20% global yield starting from the readily available 2,5-dimethoxy isoquinoline. Unprecedented regioselective control of the nucleophilic attack on the isoquinoline-5,8-dione is first described. Investigation of the possible pathways of this transformation through density functional theory calculations reveals unexpected N-oxide assistance in cascade tautomerizations, which was crucial for directing the nucleophilic attack and hastening the overall process. Using this strategy, we prepared the aniline-isoquinolinedione adduct and submitted it to an intramolecular double C-H cross-coupling activation to furnish ellipticinequinone, which gave ellipticine after a MeLi addition/BH3 reduction sequence.


Assuntos
Elipticinas , Isoquinolinas
14.
BMC Med Res Methodol ; 22(1): 276, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289496

RESUMO

INTRODUCTION: The exponential growth of published systematic reviews (SRs) presents challenges for decision makers seeking to answer clinical, public health or policy questions. In 1997, an algorithm was created by Jadad et al. to choose the best SR across multiple. Our study aims to replicate author assessments using the Jadad algorithm to determine: (i) if we chose the same SR as the authors; and (ii) if we reach the same results. METHODS: We searched MEDLINE, Epistemonikos, and Cochrane Database of SRs. We included any study using the Jadad algorithm. We used consensus building strategies to operationalise the algorithm and to ensure a consistent approach to interpretation. RESULTS: We identified 21 studies that used the Jadad algorithm to choose one or more SRs. In 62% (13/21) of cases, we were unable to replicate the Jadad assessment and ultimately chose a different SR than the authors. Overall, 18 out of the 21 (86%) independent Jadad assessments agreed in direction of the findings despite 13 having chosen a different SR. CONCLUSIONS: Our results suggest that the Jadad algorithm is not reproducible between users as there are no prescriptive instructions about how to operationalise the algorithm. In the absence of a validated algorithm, we recommend that healthcare providers, policy makers, patients and researchers address conflicts between review findings by choosing the SR(s) with meta-analysis of RCTs that most closely resemble their clinical, public health, or policy question, are the most recent, comprehensive (i.e. number of included RCTs), and at the lowest risk of bias.


Assuntos
Algoritmos , Pesquisadores , Humanos , Viés
15.
Phys Chem Chem Phys ; 24(23): 14603-14615, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35667654

RESUMO

The effect of solvent was investigated at the DFT level, M06-2X/6-31++G(d,p), for the implicit, namely the universal solvent model based on solute electron density (SMD) and hybrid solvation models, and a new pathway for the Markovnikov for the addition of HCl to 1-butene was suggested, incorporating the solvent in the reaction. The results showed that the use of implicit solvent brings greater stabilization for a large part of the reaction coordinates and for the charges of the transition states (TS). Studying the hybrid solvent model, it was shown by quantum mechanics and molecular simulations that although the first solvation shell is composed of approximately 30 solvent molecules, most of the effect comes from just eight solvent molecules explicitly added, with a variation in energy that tends to about -19.3 kJ mol-1. The reaction rates for the hydration of 1-butene were only able to achieve a reasonable accuracy with the addition of three explicit solvent molecules of 5.97 × 10-8 M-1 s-1 and 2.33 × 10-9 M-1 s-1 for the calculated and the experimental values, respectively. This indicates that not only hybrid solvation may be required, but also the number of explicit molecules added may heavily influence the calculated reaction rates. It was found that for the intermediary product of hydration the hydrogen bonds are stronger than average, suggesting a partial covalent characteristic.

16.
J Strength Cond Res ; 36(5): 1437-1444, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32868680

RESUMO

ABSTRACT: Amarante do Nascimento, M, Nunes, JPA, Pina, FLC, Ribeiro, AS, Carneiro, NH, Venturini, D, Barbosa, DS, Mayhew, JL, and Cyrino, ES. Comparison of 2 weekly frequencies of resistance training on muscular strength, body composition, and metabolic biomarkers in resistance-trained older women: Effects of detraining and retraining. J Strength Cond Res 36(5): 1437-1444, 2022-This study aimed to compare the effects of 2 weekly frequencies of resistance training (RT) on muscular strength, body composition, and metabolic biomarkers in previously resistance-trained older women after detraining and retraining. Forty subjects (>60 years) performed RT (8 exercises, 1 set of 10-15 repetitions maximum) 2 (G2x) or 3 (G3x) times per week over 12 weeks of training and retraining. After training, subjects were detrained for 12 weeks. After detraining, there were significant decreases (p < 0.05) in upper-body (∼12%) and lower-body (∼14%) muscular strength, fat-free mass (FFM) (∼2%), and testosterone (∼26%), whereas increases were revealed for fat mass (FM) (∼4%), relative body fat (∼3%), fasting glucose (∼8%), low-density lipoprotein cholesterol (LDL-C) (∼21%), and triglycerides (∼24%), with no differences between groups (p > 0.05). Following retraining, there were significant increases (p < 0.05) for upper (∼7%) and lower (∼10%) muscular strength, FFM (∼2%), and testosterone (∼20%). In contrast, decreases were found for FM (∼7%), relative body fat (∼3%), fasting glucose (∼6%), LDL-C (∼14%), and triglycerides (∼21%), also with no differences between groups (p > 0.05). Gains after retraining were lower than after training (p < 0.05) only for upper- and lower-body muscular strength (∼6%) and testosterone (∼11%). Total cholesterol, high-density lipoprotein cholesterol, IGF-1, and C-reactive protein did not change at any point in the study for either group (p > 0.05). Our results suggest that older women can regain previous RT program benefits following detraining, regardless of the weekly training frequency. However, some fitness components may take longer to reestablish than the initial training level.


Assuntos
Treinamento Resistido , Idoso , Biomarcadores , Composição Corporal , LDL-Colesterol , Feminino , Glucose , Humanos , Pessoa de Meia-Idade , Força Muscular , Músculo Esquelético , Treinamento Resistido/métodos , Testosterona , Triglicerídeos
17.
BMC Genomics ; 22(1): 239, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823806

RESUMO

BACKGROUND: Callithrix marmosets are a relatively young primate radiation, whose phylogeny is not yet fully resolved. These primates are naturally para- and allopatric, but three species with highly invasive potential have been introduced into the southeastern Brazilian Atlantic Forest by the pet trade. There, these species hybridize with each other and endangered, native congeners. We aimed here to reconstruct a robust Callithrix phylogeny and divergence time estimates, and identify the biogeographic origins of autochthonous and allochthonous Callithrix mitogenome lineages. We sequenced 49 mitogenomes from four species (C. aurita, C. geoffroyi, C. jacchus, C. penicillata) and anthropogenic hybrids (C. aurita x Callithrix sp., C. penicillata x C. jacchus, Callithrix sp. x Callithrix sp., C. penicillata x C. geoffroyi) via Sanger and whole genome sequencing. We combined these data with previously published Callithrix mitogenomes to analyze five Callithrix species in total. RESULTS: We report the complete sequence and organization of the C. aurita mitogenome. Phylogenetic analyses showed that C. aurita was the first to diverge within Callithrix 3.54 million years ago (Ma), while C. jacchus and C. penicillata lineages diverged most recently 0.5 Ma as sister clades. MtDNA clades of C. aurita, C. geoffroyi, and C. penicillata show intraspecific geographic structure, but C. penicillata clades appear polyphyletic. Hybrids, which were identified by phenotype, possessed mainly C. penicillata or C. jacchus mtDNA haplotypes. The biogeographic origins of mtDNA haplotypes from hybrid and allochthonous Callithrix were broadly distributed across natural Callithrix ranges. Our phylogenetic results also evidence introgression of C. jacchus mtDNA into C. aurita. CONCLUSION: Our robust Callithrix mitogenome phylogeny shows C. aurita lineages as basal and C. jacchus lineages among the most recent within Callithrix. We provide the first evidence that parental mtDNA lineages of anthropogenic hybrid and allochthonous marmosets are broadly distributed inside and outside of the Atlantic Forest. We also show evidence of cryptic hybridization between allochthonous Callithrix and autochthonous C. aurita. Our results encouragingly show that further development of genomic resources will allow to more clearly elucidate Callithrix evolutionary relationships and understand the dynamics of Callithrix anthropogenic introductions into the Brazilian Atlantic Forest.


Assuntos
Evolução Biológica , Callithrix , Animais , Brasil , Callithrix/genética , DNA Mitocondrial/genética , Humanos , Filogenia
18.
Chem Rev ; 119(14): 8262-8290, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30707011

RESUMO

Classically closo-carborane anions, particularly [HCB11H11]- and [HCB9H9]-, and their derivatives have primarily been used as weakly coordinating anions to isolate reactive intermediates, platforms for stoichiometric and catalytic functionalization, counteranions for simple Lewis acid catalysis, and components of materials like liquid crystals. The aim of this article is to educate the reader on the contemporary nonclassical applications of these anions. Specifically, this review will cover new directions in main group catalysis utilized to achieve some of the most challenging catalytic reactions such as C-F, C-H, and C-C functionalizations that are difficult or impossible to realize with transition metals. In addition, the review will cover the utilization of the clusters as dianionic C σ-bound ligands for coordination chemistry, ligand substituents for coordination chemistry and advanced catalyst design, and covalently bound spectator substituents to stabilize radicals. Furthermore, their applications as solution-based and solid-state electrolytes for Li, Na, and Mg batteries will be discussed.

19.
BJOG ; 128(7): 1236-1246, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33300296

RESUMO

OBJECTIVE: To compare intramuscular oxytocin, Syntometrine® and carbetocin for prevention of postpartum haemorrhage after vaginal birth. DESIGN: Randomised double-blinded clinical trial. SETTING: Six hospitals in England. POPULATION: A total of 5929 normotensive women having a singleton vaginal birth. METHODS: Randomisation when birth was imminent. MAIN OUTCOME MEASURES: Primary: use of additional uterotonic agents. Secondary: weighed blood loss, transfusion, manual removal of placenta, adverse effects, quality of life. RESULTS: Participants receiving additional uterotonics: 368 (19.5%) oxytocin, 298 (15.6%) Syntometrine and 364 (19.1%) carbetocin. When pairwise comparisons were made: women receiving carbetocin were significantly more likely to receive additional uterotonics than those receiving Syntometrine (odds ratio [OR] 1.28, 95% CI 1.08-1.51, P = 0.004); the difference between carbetocin and oxytocin was non-significant (P = 0.78); Participants receiving Syntometrine were significantly less likely to receive additional uterotonics than those receiving oxytocin (OR 0.75, 95% CI 0.65-0.91, P = 0.002). Non-inferiority between carbetocin and Syntometrine was not shown. Use of Syntometrine reduced non-drug PPH treatments compared with oxytocin (OR 0.64, 95% CI 0.42-0.97) but not carbetocin (P = 0.64). Rates of PPH and blood transfusion were not different. Syntometrine was associated with an increase in maternal adverse effects and reduced ability of the mother to bond with her baby. CONCLUSIONS: Non-inferiority of carbetocin to Syntometrine was not shown. Carbetocin is not significantly different to oxytocin for use of additional uterotonics. Use of Syntometrine reduced use of additional uterotonics and need for non-drug PPH treatments compared with oxytocin. Increased maternal adverse effects are a disadvantage of Syntometrine. TWEETABLE ABSTRACT: IM carbetocin does not reduce additional uterotonic use compared with IM Syntometrine or oxytocin.


Assuntos
Ergonovina/uso terapêutico , Ocitócicos/uso terapêutico , Ocitocina/análogos & derivados , Ocitocina/uso terapêutico , Hemorragia Pós-Parto/prevenção & controle , Adulto , Transfusão de Sangue/estatística & dados numéricos , Parto Obstétrico , Método Duplo-Cego , Feminino , Humanos , Hipertensão/epidemiologia , Injeções Intramusculares , Gravidez , Transtornos Puerperais/epidemiologia , Qualidade de Vida
20.
Biometals ; 34(4): 831-840, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33913063

RESUMO

Selenium is an essential element in human and animal metabolism integrated into the catalytic site of glutathione peroxidase (GPX1), an antioxidant enzyme that protects cells from damage caused by reactive oxygen species (ROS). Oxidative stress refers the imbalance between ROS and antioxidant defense systems. It generates alterations of DNA, proteins and lipid peroxidation. The imbalance occurs particularly during ischemia and lack of postmortem perfusion. This mechanism is of relevance in transplant organs, affecting their survival. The aim of this research is to evaluate the effect of seleno-methionine (SeMet) as a protective agent against postmortem ischemia injury in transplant organs. Wistar rats were orally administered with SeMet. After sacrifice, liver, heart and kidney samples were collected at different postmortem intervals (PMIs). SeMet administration produced a significant increase of Se concentration in the liver (65%, p < 0.001), heart (40%, p < 0.01) and kidneys (45%, p < 0.05). Levels of the oxidative stress marker malondialdehyde (MDA) decreased significantly compared to control in the heart (0.21 ± 0.04 vs. 0.12 ± 0.02 mmol g-1) and kidneys (0.41 ± 0.02 vs. 0.24 ± 0.03 mmol g-1) in a PMI of 1-12 h (p < 0.01). After SeMet administration for 21 days, a significant increase in GPX1 activity was observed in the liver (80%, p < 0.001), kidneys (74%, p < 0.01) and heart (35%, p < 0.05). SeMet administration to rats significantly decreased the oxidative stress in the heart, liver and kidneys of rats generated by postmortem ischemia.


Assuntos
Coração , Isquemia/metabolismo , Rim/metabolismo , Fígado/metabolismo , Selenometionina/metabolismo , Administração Oral , Animais , Feminino , Estresse Oxidativo , Ratos , Ratos Wistar , Selenometionina/administração & dosagem , Selenometionina/análise
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