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1.
Nature ; 621(7980): 716-722, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37758891

RESUMEN

Einstein's general theory of relativity from 19151 remains the most successful description of gravitation. From the 1919 solar eclipse2 to the observation of gravitational waves3, the theory has passed many crucial experimental tests. However, the evolving concepts of dark matter and dark energy illustrate that there is much to be learned about the gravitating content of the universe. Singularities in the general theory of relativity and the lack of a quantum theory of gravity suggest that our picture is incomplete. It is thus prudent to explore gravity in exotic physical systems. Antimatter was unknown to Einstein in 1915. Dirac's theory4 appeared in 1928; the positron was observed5 in 1932. There has since been much speculation about gravity and antimatter. The theoretical consensus is that any laboratory mass must be attracted6 by the Earth, although some authors have considered the cosmological consequences if antimatter should be repelled by matter7-10. In the general theory of relativity, the weak equivalence principle (WEP) requires that all masses react identically to gravity, independent of their internal structure. Here we show that antihydrogen atoms, released from magnetic confinement in the ALPHA-g apparatus, behave in a way consistent with gravitational attraction to the Earth. Repulsive 'antigravity' is ruled out in this case. This experiment paves the way for precision studies of the magnitude of the gravitational acceleration between anti-atoms and the Earth to test the WEP.

2.
Proc Natl Acad Sci U S A ; 120(31): e2306046120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37487099

RESUMEN

The electron-conducting circuitry of life represents an as-yet untapped resource of exquisite, nanoscale biomolecular engineering. Here, we report the characterization and structure of a de novo diheme "maquette" protein, 4D2, which we subsequently use to create an expanded, modular platform for heme protein design. A well-folded monoheme variant was created by computational redesign, which was then utilized for the experimental validation of continuum electrostatic redox potential calculations. This demonstrates how fundamental biophysical properties can be predicted and fine-tuned. 4D2 was then extended into a tetraheme helical bundle, representing a 7 nm molecular wire. Despite a molecular weight of only 24 kDa, electron cryomicroscopy illustrated a remarkable level of detail, indicating the positioning of the secondary structure and the heme cofactors. This robust, expressible, highly thermostable and readily designable modular platform presents a valuable resource for redox protein design and the future construction of artificial electron-conducting circuitry.


Asunto(s)
Hemoproteínas , Biofisica , Microscopía por Crioelectrón , Electrones , Oxidación-Reducción
3.
Biochemistry ; 63(11): 1493-1504, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38742407

RESUMEN

DNA gyrases catalyze negative supercoiling of DNA, are essential for bacterial DNA replication, transcription, and recombination, and are important antibacterial targets in multiple pathogens, including Mycobacterium tuberculosis, which in 2021 caused >1.5 million deaths worldwide. DNA gyrase is a tetrameric (A2B2) protein formed from two subunit types: gyrase A (GyrA) carries the breakage-reunion active site, whereas gyrase B (GyrB) catalyzes ATP hydrolysis required for energy transduction and DNA translocation. The GyrB ATPase domains dimerize in the presence of ATP to trap the translocated DNA (T-DNA) segment as a first step in strand passage, for which hydrolysis of one of the two ATPs and release of the resulting inorganic phosphate is rate-limiting. Here, dynamical-nonequilibrium molecular dynamics (D-NEMD) simulations of the dimeric 43 kDa N-terminal fragment of M. tuberculosis GyrB show how events at the ATPase site (dissociation/hydrolysis of bound nucleotides) are propagated through communication pathways to other functionally important regions of the GyrB ATPase domain. Specifically, our simulations identify two distinct pathways that respectively connect the GyrB ATPase site to the corynebacteria-specific C-loop, thought to interact with GyrA prior to DNA capture, and to the C-terminus of the GyrB transduction domain, which in turn contacts the C-terminal GyrB topoisomerase-primase (TOPRIM) domain responsible for interactions with GyrA and the centrally bound G-segment DNA. The connection between the ATPase site and the C-loop of dimeric GyrB is consistent with the unusual properties of M. tuberculosis DNA gyrase relative to those from other bacterial species.


Asunto(s)
Adenosina Trifosfatasas , Girasa de ADN , Simulación de Dinámica Molecular , Mycobacterium tuberculosis , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/genética , Girasa de ADN/metabolismo , Girasa de ADN/química , Girasa de ADN/genética , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/genética , Dominios Proteicos , Adenosina Trifosfato/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Transducción de Señal
4.
J Biol Chem ; 299(8): 105014, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37414149

RESUMEN

The target for humoral immunity, SARS-CoV-2 spike glycoprotein, has become the focus of vaccine research and development. Previous work demonstrated that the N-terminal domain (NTD) of SARS-CoV-2 spike binds biliverdin-a product of heme catabolism-causing a strong allosteric effect on the activity of a subset of neutralizing antibodies. Herein, we show that the spike glycoprotein is also able to bind heme (KD = 0.5 ± 0.2 µM). Molecular modeling indicated that the heme group fits well within the same pocket on the SARS-CoV-2 spike NTD. Lined by aromatic and hydrophobic residues (W104, V126, I129, F192, F194, I203, and L226), the pocket provides a suitable environment to stabilize the hydrophobic heme. Mutagenesis of N121 has a substantive effect on heme binding (KD = 3000 ± 220 µM), confirming the pocket as a major heme binding location of the viral glycoprotein. Coupled oxidation experiments in the presence of ascorbate indicated that the SARS-CoV-2 glycoprotein can catalyze the slow conversion of heme to biliverdin. The heme trapping and oxidation activities of the spike may allow the virus to reduce levels of free heme during infection to facilitate evasion of the adaptive and innate immunity.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Anticuerpos Antivirales , Biliverdina , Receptores Virales/metabolismo , Anticuerpos Neutralizantes
5.
J Biol Chem ; 299(6): 104702, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37059182

RESUMEN

Mitochondria are organelles known primarily for generating ATP via the oxidative phosphorylation process. Environmental signals are sensed by whole organisms or cells and markedly affect this process, leading to alterations in gene transcription and, consequently, changes in mitochondrial function and biogenesis. The expression of mitochondrial genes is finely regulated by nuclear transcription factors, including nuclear receptors and their coregulators. Among the best-known coregulators is the nuclear receptor corepressor 1 (NCoR1). Muscle-specific knockout of NCoR1 in mice induces an oxidative phenotype, improving glucose and fatty acid metabolism. However, the mechanism by which NCoR1 is regulated remains elusive. In this work, we identified the poly(A)-binding protein 4 (PABPC4) as a new NCoR1 interactor. Unexpectedly, we found that silencing of PABPC4 induced an oxidative phenotype in both C2C12 and MEF cells, as indicated by increased oxygen consumption, mitochondria content, and reduced lactate production. Mechanistically, we demonstrated that PABPC4 silencing increased the ubiquitination and consequent degradation of NCoR1, leading to the derepression of PPAR-regulated genes. As a consequence, cells with PABPC4 silencing had a greater capacity to metabolize lipids, reduced intracellular lipid droplets, and reduced cell death. Interestingly, in conditions known to induce mitochondrial function and biogenesis, both mRNA expression and PABPC4 protein content were markedly reduced. Our study, therefore, suggests that the lowering of PABPC4 expression may represent an adaptive event required to induce mitochondrial activity in response to metabolic stress in skeletal muscle cells. As such, the NCoR1-PABPC4 interface might be a new road to the treatment of metabolic diseases.


Asunto(s)
Receptores Citoplasmáticos y Nucleares , Factores de Transcripción , Animales , Ratones , Proteínas Co-Represoras/metabolismo , Co-Represor 1 de Receptor Nuclear/genética , Co-Represor 1 de Receptor Nuclear/metabolismo , Fosforilación Oxidativa , Receptores Citoplasmáticos y Nucleares/metabolismo , Estrés Fisiológico , Factores de Transcripción/metabolismo
6.
J Am Chem Soc ; 146(1): 901-919, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38116743

RESUMEN

Protein functions are dynamically regulated by allostery, which enables conformational communication even between faraway residues, and expresses itself in many forms, akin to different "languages": allosteric control pathways predominating in an unperturbed protein are often unintuitively reshaped whenever biochemical perturbations arise (e.g., mutations). To accurately model allostery, unbiased molecular dynamics (MD) simulations require integration with a reliable method able to, e.g., detect incipient allosteric changes or likely perturbation pathways; this is because allostery can operate at longer time scales than those accessible by plain MD. Such methods are typically applied singularly, but we here argue their joint application─as a "multilingual" approach─could work significantly better. We successfully prove this through unbiased MD simulations (∼100 µs) of the widely studied, allosterically active oncotarget K-Ras4B, solvated and embedded in a phospholipid membrane, from which we decrypt allostery using four showcase "languages": Distance Fluctuation analysis and the Shortest Path Map capture allosteric hotspots at equilibrium; Anisotropic Thermal Diffusion and Dynamical Non-Equilibrium MD simulations assess perturbations upon, respectively, either superheating or hydrolyzing the GTP that oncogenically activates K-Ras4B. Chosen "languages" work synergistically, providing an articulate, mutually coherent, experimentally consistent picture of K-Ras4B allostery, whereby distinct traits emerge at equilibrium and upon GTP cleavage. At equilibrium, combined evidence confirms prominent allosteric communication from the membrane-embedded hypervariable region, through a hub comprising helix α5 and sheet ß5, and up to the active site, encompassing allosteric "switches" I and II (marginally), and two proposed pockets. Upon GTP cleavage, allosteric perturbations mostly accumulate on the switches and documented interfaces.


Asunto(s)
Simulación de Dinámica Molecular , Proteínas , Proteínas/química , Dominio Catalítico , Guanosina Trifosfato/metabolismo , Regulación Alostérica
7.
J Endocrinol Invest ; 47(2): 421-432, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37550552

RESUMEN

PURPOSE: PRESTO 3 evaluated nurses' preference for the Somatuline® Autogel® syringe versus the Lanreotide Pharmathen syringe after injection-pad testing. METHODS: This international simulated-use study included oncology/endocrinology nurses with ≥ 1 years' experience in managing neuroendocrine tumours (NETs) and/or acromegaly. Each nurse tested both syringes twice in a randomised order before completing an electronic survey. The primary objective was to assess overall preference (%, 95% confidence interval [CI]) for the Somatuline Autogel syringe versus the Lanreotide Pharmathen syringe. Secondary objectives included rating syringe performance and ranking the importance of syringe attributes. RESULTS: Ninety-four nurses were enrolled: mean age, 41.0 (SD, 11.5) years. The percentage of nurses stating a preference ("strong" or "slight") for the Somatuline Autogel syringe (86.2% [95% CI 77.5-92.4%]) was significantly higher than 50% (p < 0.0001). Performance rating was significantly higher for the Somatuline Autogel syringe versus Lanreotide Pharmathen syringe for 10 of the 11 attributes tested (p < 0.05). The syringe attributes considered most important when injecting patients in routine clinical practice were "easy to use from preparation to injection" (30.9%) and "comfortable to handle during use from preparation to injection" (16.0%). The attribute most commonly rated as least important was "fast administration from preparation to injection" (26.6%). CONCLUSION: Nurses strongly preferred the user experience of the Somatuline Autogel syringe over the Lanreotide Pharmathen syringe. "Ease of use" and "comfortable to handle" were the most important syringe attributes, and performance rating was significantly higher with Somatuline Autogel versus Lanreotide Pharmathen syringe for all but one attribute.


Drugs called somatostatin analogues (SSAs) can be used to treat patients with neuroendocrine tumours or acromegaly over a prolonged period of time. SSAs are given as injections and act by slowing the production of hormones by the body and in some cases reducing the growth of the tumour. To help to provide the best care possible, it is important that the syringe used for the injection is easy to use and delivers the SSA effectively. Somatuline Autogel is a syringe that can be used to inject an SSA called lanreotide. Previous studies showed that patients and nurses preferred the injection experience when using the Somatuline Autogel syringe compared with a syringe used to inject another SSA called octreotide long-acting release. A new syringe used for lanreotide injections has been developed recently by a company called Pharmathen. In the PRESTO 3 study, we compared the user experience of the Somatuline Autogel syringe and the Lanreotide Pharmathen syringe. We asked 94 nurses from Europe and the US to test both syringes, in a randomised order, using injection pads, and then to answer questions about their overall preference between the two syringes and how well the syringe performed for a set of syringe features. Overall, 86% of nurses preferred the Somatuline Autogel syringe over the Lanreotide Pharmathen syringe. Of the 11 features of the syringe that we assessed, 10 were rated higher for the Somatuline Autogel syringe than the Lanreotide Pharmathen syringe. The syringe features "ease of use" and "comfortable to handle" were considered the most important. The results of the PRESTO 3 study indicated that there is a difference in the user experience between the syringes, particularly for confidence and ease of use, and that it is important to offer syringe choices to nurses who are using SSA injections to treat patients.


Asunto(s)
Acromegalia , Tumores Neuroendocrinos , Enfermeras y Enfermeros , Somatostatina/análogos & derivados , Humanos , Adulto , Acromegalia/tratamiento farmacológico , Jeringas , Péptidos Cíclicos
8.
J Dairy Sci ; 107(3): 1472-1484, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37944809

RESUMEN

Asparagopsis taxiformis inhibits ruminal methane (CH4) production due to its bromoform (CHBr3) content. The immersion of A. taxiformis in edible vegetable oils allows the extraction and stabilization of the highly volatile CHBr3 in the oil phase. The objectives of this study were to explore the effects of adding sunflower oils with increasing concentrations of CHBr3 on in vitro ruminal methanogenesis and biohydrogenation. Five batches of 48-h in vitro incubations were performed in 14 fermentation bottles, using rumen inocula collected shortly after the slaughter of young crossbred bulls and 1 g of dry matter (DM) from a total diet of mixed feed without added oil (control) or with 60 µL of sunflower oil per gram of DM as the substrate. The treatments were the CHBr3 content in the oil added: 0 µg (B0), 25 µg (B25), 50 µg (B50), 75 µg (B75), 100 µg (B100), and 150 µg (B150) of CHBr3 per gram of substrate DM. Organic matter (OM) degradability, total gas, CH4, volatile fatty acids (VFA), long-chain fatty acids, and dimethyl acetals (DMA) were analyzed at the end of each incubation. Data were analyzed with a model considering the treatments as the fixed effect and the run as a random block and using orthogonal contrasts. Degradability of OM was higher in the control group and was unaffected by CHBr3 concentration. Total gas production per gram of degraded OM was unaffected by treatments and averaged 205 ± 29.8 mL/g. Methane (mL) production decreased linearly with increasing CHBr3 concentrations, with 33%, 47%, and 87% reductions for B75, B100, and B150, respectively. Total VFA concentration was unaffected by oil inclusion but was reduced by 20% in CHBr3-containing treatments, although without any dose-response pattern. The molar percentage of acetate decreased linearly, whereas propionate and butyrate increased linearly with the increasing CHBr3 dosage. Including oil in the diet decreased the branched-chain fatty acids and DMA content. Increasing CHBr3 concentrations did not affect branched-chain fatty acids, but linearly increased most of the identified DMA. Adding oil to the control diet increased the 18:2n-6, whereas increasing the concentration of CHBr3 had no effect on 18:2n-6 but decreased linearly the 18:0 and increased the trans-18:1 isomers. The results obtained provide evidence that oil immersions of A. taxiformis can successfully inhibit ruminal production of CH4 in vitro at doses of 100 and 150 µg/g DM, and simultaneously modulate biohydrogenation.


Asunto(s)
Acetales , Ácidos Grasos Insaturados , Ácidos Grasos , Rhodophyta , Animales , Bovinos , Masculino , Aceite de Girasol , Metano
9.
J Dairy Sci ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38788835

RESUMEN

In this study, the main objective was to assess if long luteal phases could have other causes than pregnancy losses. We enrolled Holstein dairy cows ≥50 d in milk (DIM) from a commercial herd in Brazil from October 2016 to August 2017. All cows received an estradiol-based synchronization protocol, and, on the day of insemination (d 0), were randomly assigned either an artificial insemination (AI) or a placebo insemination (PBO) in a 3:1 ratio. An ultrasound was used to assess the presence of a CL on d17, 24, and 31, which, combined to the information from patches for the detection of estrus, was used to determine the length of the luteal phase following AI or PBO. Pregnancy was assessed by ultrasound on d 31 and cows that were pregnant were excluded from the analyses. The length of the estrous cycles was categorized as short (<17 d), normal (17-23 d), long (24-30 d), and very long (≥31 d). We compared the proportion of cows in each category between the AI and PBO groups using a cumulative ordinal mixed model. We define prolonged luteal phase as estrous cycles ≥24 d and tested its association with potential risk factors (parity, season, DIM, uterine size and position score, milk production, body condition score, and the presence of a corpus luteum (CL) at enrollment to the synchronization protocol) using mixed logistic regression models. Results are presented as odds ratio (OR) and 95% credible intervals (BCI). Data from 876 inseminations (AI: n = 616, PBO: n = 260) was collected. Overall, 12% of estrous cycles were short, 31% were normal, 19% were long, and 38% were very long. There was no difference in the odds of being in longer estrous cycle categories for the AI compared with the PBO group (OR = 0.92, 95% BCI = 0.76-1.10). Season and presence of a CL at enrollment were associated with prolonged luteal phase. In the AI group, there was a possible effect of early pregnancy losses on the lifespan of the CL, but not the PBO group, which led us to conclude that long and very long estrous cycles were not all caused by the embryonic loss. In fact, the high prevalence of cows with an extended CL lifespan in the present study suggests this could be an under- or miss-reported characteristic of high-producing lactating Holstein cows. This finding may have important repercussions in the understanding of the CL function physiology of lactating Holstein cows.

10.
J Dairy Sci ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38608938

RESUMEN

Our objective was to estimate the requirements of metabolizable energy (ME) and net energy for the maintenance (NEm) of lactating and dry cows, the efficiency of ME utilization for milk production (kl) and tissue gain (kg), and the use of body energy mobilization for milk production (kt) throughout the lactation of primiparous crossbred Holstein × Gyr cows, using open-circuit respiration chambers. Twenty-nine primiparous Holstein × Gyr crossbred cows with an initial BW averaging 563 ± 40.1 kg and 2.5 ± 0.09 years old were used throughout lactation and dry periods. The cows were kept non-pregnant throughout the study to eliminate possible confounding factors. Apparent digestibility assays, followed by calorimeter measurements, were performed 6 times throughout the lactation period. In the dry-off period, the cows were also evaluated but fed with restricted intake (DMI = 1.1% BW/d) to achieve heat production close to maintenance. After 21 d of diet adaptation, an apparent digestibility assay followed by calorimeter measurements was performed. Parameter estimates for lactation period were obtained by mixed models including lactation stage as repeated measures. For restricted feeding at dry-off and fasting period assays, the requirements were estimated by exponential regression. For whole lactation, the values of MEm and NEm were 0.588 and 0.395 MJ/BW0.75, respectively. The efficiencies klkgkt were 0.672, 0.771, and 0.814, respectively. However, MEm and NEm were higher in early and mid-lactation than late, while kl was higher in early than other lactation stages. Dry and non-pregnant cows had MEm of 0.434 MJ/BW0.75 and NEm of 0.351 MJ/BW0.75 for maintenance level, and MEm of 0.396 MJ/BW0.75 and NEm of 0.345 MJ/BW0.75 for fasting metabolism level and efficiency of ME utilization for maintenance was 0.80. Our findings confirmed that F1 crossbred Holstein × Gyr dairy cows have differences in energy requirement and efficiency throughout the lactation stages, suggesting the use of different values in each stage. The estimated values of energy requirement for maintenance and efficiencies for primiparous lactating crossbred Holstein × Gyr were similar to those reported in the literature in specific studies and requirements systems.

11.
Public Health ; 232: 195-200, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38805868

RESUMEN

OBJECTIVE: This study investigated the associations of occupational physical activity and active transport with depressive symptoms, stratified by income range, among Brazilian working adults. STUDY DESIGN: This cross-sectional study drew on data from the 2019 Brazilian National Health Survey. METHODS: We used the Patient Health Questionnaire (PHQ-9) to assess depressive symptoms in working adults aged 18-65 years, with physical activities (occupational physical activity and active transport) self-reported through a specially developed questionnaire. Crude and adjusted logistic regression models were fitted. RESULTS: Individuals at the highest level of occupational physical activity (odds ratio [OR] 1.35; 95% confidence interval [95% CI] 1.19-1.53) and at the moderate level of active transport to work (OR 1.66; 95% CI 1.24-2.22) returned increased odds of depressive symptoms as compared with those who were inactive in these domains. Stratified by income group, light active transport to work (OR 0.57; 95% CI 0.34-0.95) in the lower income group (Range 1) was associated with lower odds of depressive symptoms. On the other hand, individuals at the highest level of active transport to work returned higher odds of depressive symptoms in the low- and intermediate-income groups, Ranges 3 and 4 (OR 1.92; 95% CI 1.22-3.00 and OR 2.91; 95% CI 1.71-4.95, respectively). CONCLUSION: Our results suggest that occupational physical activity and active transport may be a risk factor for depressive symptoms. They also point to differences in this relationship by income range. Further studies are needed to pursue the analysis of how specific domains of physical activity contribute to depressive symptoms.


Asunto(s)
Depresión , Ejercicio Físico , Humanos , Adulto , Persona de Mediana Edad , Masculino , Femenino , Ejercicio Físico/psicología , Estudios Transversales , Brasil/epidemiología , Depresión/epidemiología , Depresión/psicología , Adulto Joven , Adolescente , Anciano , Transportes/estadística & datos numéricos , Renta/estadística & datos numéricos , Encuestas Epidemiológicas
12.
J Oral Rehabil ; 51(7): 1303-1319, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38572886

RESUMEN

INTRODUCTION: The selection of appropriate outcomes in clinical trials and systematic reviews is a crucial factor in determining the results that are useful, reliable, and relevant for both patients and healthcare professionals. Clinicians and researchers have been encouraged to develop and apply core outcome sets (COS) to minimise the discrepancy between studies. AIM: This systematic review is the first phase of the COS development project for clinical trials in temporomandibular disorders (COS-TMD). It aims to identify and synthesise the outcomes used in the randomised controlled trials (RCT) that evaluated the effectiveness of interventions used in TMD management. MATERIALS AND METHODS: An electronic search was performed in several databases: MEDLINE (via PubMed), Scopus, Web of Science, Cochrane Library and EMBASE. The eligibility criteria comprised RCT that applied any intervention to treat temporomandibular joint disorders or masticatory muscle disorders. The identified outcomes were categorised according to domains of the Initiative on Methods, Measurement and Pain Assessment in Clinical Trials (IMMPACT). RESULTS: The electronic search resulted in 1606 studies. After removing duplicates and applying the eligibility criteria, 106 RCT were included. A total of 43 studies evaluated masticatory muscle disorders, 27 evaluated temporomandibular joint disorders, and 36 analysed mixed TMD. CONCLUSIONS: The evaluation showed significant variability in the types of outcomes and their measurement instruments. In addition, some domains such as physical and emotional functioning, participant ratings of global improvement and adverse events have been neglected when determining the effectiveness of treatments for TMD.


Asunto(s)
Trastornos de la Articulación Temporomandibular , Humanos , Trastornos de la Articulación Temporomandibular/terapia , Trastornos de la Articulación Temporomandibular/fisiopatología , Evaluación de Resultado en la Atención de Salud , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Dimensión del Dolor
13.
J Helminthol ; 98: e5, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38167304

RESUMEN

During the study of ectoparasites (Platyhelminthes) of fish in the floodplain of the Upper Paraná River - Brazil, a new species of Urocleidoides, present in the gill filaments of Hemiodus orthonops (Hemiodontidae), is described using morphological description and molecular data from the mitochondrial region of cytochrome c oxidase, subunit 1 (COI) and the partial region of the 28S rDNA gene. Urocleidoides luquei n. sp. differs from all its congeners by the presence of a filament that joins the accessory piece to the base of the male copulatory organ and resembles U. paradoxus and U. surianoae. Phylogenetic analyses using molecular data revealed that U. luquei n. sp. forms a paraphyletic group concerning the other Urocleidoides species. In this way, as well as contributing to the description of a new species, we seek to encourage and contribute to the increase in research using integrative taxonomy, thus making it possible to elucidate some unresolved questions about the genus Urocleidoides.


Asunto(s)
Characiformes , Enfermedades de los Peces , Parásitos , Trematodos , Masculino , Animales , Ríos/parasitología , Filogenia , Brasil , Characiformes/parasitología , Branquias/parasitología , Enfermedades de los Peces/parasitología
14.
Pituitary ; 26(1): 9-41, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36447058

RESUMEN

PURPOSE: This systematic literature review investigated whether extended dosing intervals (EDIs) of pharmacological acromegaly treatments reduce patient burden and costs compared with standard dosing, while maintaining effectiveness. METHODS: MEDLINE/Embase/the Cochrane Library (2001-June 2021) and key congresses (2018-2021) were searched and identified systematic literature review bibliographies reviewed. Included publications reported on efficacy/effectiveness, safety and tolerability, health-related quality of life (HRQoL), and patient-reported and economic outcomes in longitudinal/cross-sectional studies in adults with acromegaly. Interventions included EDIs of pegvisomant, cabergoline, and somatostatin receptor ligands (SRLs): lanreotide autogel/depot (LAN), octreotide long-acting release (OCT), pasireotide long-acting release (PAS), and oral octreotide; no comparator was required. RESULTS: In total, 35 publications reported on 27 studies: 3 pegvisomant monotherapy, 11 pegvisomant combination therapy with SRLs, 9 LAN, and 4 OCT; no studies reported on cabergoline, PAS, or oral octreotide at EDIs. Maintenance of normal insulin-like growth factor I (IGF-I) was observed in ≥ 70% of patients with LAN (1 study), OCT (1 study), and pegvisomant monotherapy (1 study). Achievement of normal IGF-I was observed in ≥ 70% of patients with LAN (3 studies) and pegvisomant in combination with SRLs (4 studies). Safety profiles were similar across EDI and standard regimens. Patients preferred and were satisfied with EDIs. HRQoL was maintained and cost savings were provided with EDIs versus standard regimens. CONCLUSIONS: Clinical efficacy/effectiveness, safety, and HRQoL outcomes in adults with acromegaly were similar and costs lower with EDIs versus standard regimens. Physicians may consider acromegaly treatment at EDIs, especially for patients with good disease control.


Asunto(s)
Acromegalia , Hormona de Crecimiento Humana , Adulto , Humanos , Acromegalia/tratamiento farmacológico , Acromegalia/metabolismo , Octreótido/uso terapéutico , Factor I del Crecimiento Similar a la Insulina/metabolismo , Cabergolina/uso terapéutico , Estudios Transversales , Calidad de Vida , Péptidos Cíclicos/uso terapéutico , Hormona de Crecimiento Humana/uso terapéutico , Hormona de Crecimiento Humana/metabolismo
15.
Regul Toxicol Pharmacol ; 143: 105459, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37474097

RESUMEN

The unexpected finding of N-nitrosamine (NA) impurities in many pharmaceutical products raised significant challenges for industry and regulators. In addition to well-studied small molecular weight NAs, many of which are potent rodent carcinogens, novel NAs associated with active pharmaceutical ingredients have been found, many of which have limited or no safety data. A tiered approach to establishing Acceptable Intake (AI) limits for NA impurities has been established using chemical-specific data, read-across, or a class-specific TTC limit. There are ∼140 NAs with some rodent carcinogenicity data, but much of it is older and does not meet current guidelines for what constitutes a 'robust' bioassay. Nevertheless, these data are an important source of information to ensure the best science is used for assessing NA impurities and assuring consumer safety while minimizing impact that can lead to drug shortages. We present several strategies to maximize the use of imperfect data including using a lower confidence limit on a rodent TD50, and leveraging data from multiple NAs. Information on the chemical structure known to impact potency can also support development of an AI or potentially conclude that a particular NA does not fall in the cohort of concern for potent carcinogenicity.


Asunto(s)
Mutágenos , Nitrosaminas , Mutágenos/toxicidad , Mutágenos/química , Contaminación de Medicamentos , Medición de Riesgo , Carcinógenos/toxicidad , Carcinógenos/química , Preparaciones Farmacéuticas
16.
Zygote ; 31(2): 173-179, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36804925

RESUMEN

Carvacrol (C10H14O), an efficient phenolic antioxidant substance for several cell types, may become a useful antioxidant for female germ cells and embryo culture. This study investigates the effects of carvacrol supplementation on bovine oocytes in in vitro maturation (IVM) and embryo production. In total, 1222 cumulus-oocyte complexes were cultured in TCM-199+ alone (control treatment) or supplemented with carvacrol at the concentrations of 3 µM (Carv-3), 12.5 µM (Carv-12.5), or 25 µM (Carv-25). After IVM, the oocytes were subjected to in vitro fertilization and embryo production, and the spent medium post-IVM was used for evaluating the levels of reactive oxygen species and the antioxidant capacity (2,2-diphenyl-1-picryl-hydrazyl-hydrate and 2,2'-azinobis-3-ethyl-benzothiozoline-6-sulphonic acid quantification). A greater (P < 0.05) antioxidant potential was observed in the spent medium of all carvacrol-treated groups compared with the control medium. Moreover, the addition of carvacrol to the maturation medium did not affect (P > 0.05) blastocyst production on days 7 and 10 of culture; however, the total number of cells per blastocyst was reduced (P < 0.05) in two carvacrol-treated groups (Carv-3 and Carv-25). In conclusion, carvacrol demonstrated a high antioxidant capacity in the spent medium after oocyte maturation; however, although embryo production was not affected, in general, carvacrol addition to IVM medium reduced the total number of cells per blastocyst. Therefore, due to the high antioxidant capacity of carvacrol, new experiments are warranted to investigate the beneficial effects of lower concentrations of carvacrol on embryo production in cattle and other species.


Asunto(s)
Antioxidantes , Técnicas de Maduración In Vitro de los Oocitos , Bovinos , Femenino , Animales , Antioxidantes/farmacología , Antioxidantes/metabolismo , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oogénesis , Oocitos , Fertilización In Vitro/veterinaria , Blastocisto
17.
Public Health ; 220: 80-87, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37276777

RESUMEN

OBJECTIVES: This study aimed to prospectively explore the association between early lifetime exposure to psychosocial adversity and engagement in health risk behaviours (HRBs) during early adolescence. STUDY DESIGN: This was a prospective study. METHODS: This study used data from the baseline (2005-2006), third (2016-2017) and fourth waves (2018-2020) of the Generation XXI birth cohort. Socio-economic circumstances (SECs) at baseline, adverse childhood experiences (ACEs; e.g. abuse, neglect, household dysfunction) at age 10 years and HRBs (i.e. alcohol consumption, smoking, physical exercise level, sedentary behaviours, sleep duration and eating behaviours) at age 13 years were measured. Patterns of HRBs were obtained using latent class analysis. Latent class regression analysis was used to estimate the likelihood of being engaged in HRBs according to the extent of exposure to ACEs (i.e. 0 ACEs, 1-3 ACEs, 4-5 ACEs and ≥6 ACEs) and negative family SECs. RESULTS: Adolescents whose mothers had a low level of education (adjusted odds ratio [aOR] = 2.72 [95% confidence interval {CI}, 2.33-3.18]), low occupational status (aOR = 3.21 [95% CI, 2.68-3.85]) and low income (aOR = 2.70 [95% CI, 2.23-3.28]) were more likely to be engaged in HRBs than their peers with higher SECs. Adolescents who experienced more ACEs were at a significantly increased risk of involvement in HRBs (aOR = 1.86 [95% CI, 1.33-2.63] for 4-5 ACEs vs aOR 2.41 [95% CI, 1.72-3.43] for ≥6 ACEs). No significant gender differences were observed. CONCLUSIONS: Adolescents from families with low SECs were more likely than their more affluent counterparts to be engaged in HRBs. Furthermore, more ACEs contributed to widening health inequalities.


Asunto(s)
Maltrato a los Niños , Conductas de Riesgo para la Salud , Humanos , Niño , Adolescente , Estudios Prospectivos , Cohorte de Nacimiento , Maltrato a los Niños/psicología , Análisis por Conglomerados
18.
Public Health ; 225: 311-319, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37972494

RESUMEN

OBJECTIVES: In 2020, Brazil experienced two concurrent public health challenges related to respiratory disease: wildfires and increased mortality due to the coronavirus (COVID-19) pandemic. Smoke from these wildfires contributed to a variety of air pollutants, including fine particulate matter (PM2.5). The present study aims to investigate the effects of environmental and socio-economic factors on COVID-19 hospitalisation in the Pantanal. STUDY DESIGN: Ecological retrospective study. METHODS: We applied a multilevel negative binomial model to relate monthly hospitalisation data with environmental variables. RESULTS: We showed that monthly PM2.5 concentration levels had the greatest influence on the increase in hospitalisations by COVID-19 in the elderly (23 % increase). The Gini index, a coefficient that reflects income inequalities, also had a positive association with COVID-19 hospitalisations (18 % increase). Higher temperatures and humidity were protective factors, showing a 15 % and 14 % decrease in hospitalisations, respectively. The results of the present study suggest that high PM2.5 exposure contributed to the increase in COVID-19 hospitalisations, as did the social inequalities of each municipality. CONCLUSIONS: The present study highlights the importance of gathering evidence supported by multiple information sources to guide decision-making and identify populations needing better public health systems.


Asunto(s)
COVID-19 , Incendios Forestales , Humanos , Anciano , Humo/efectos adversos , Humedales , Estudios Retrospectivos , Brasil/epidemiología , COVID-19/epidemiología , Material Particulado/análisis
19.
J Helminthol ; 97: e9, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36648225

RESUMEN

A new species of Ancyracanthus, parasite of the electric eel Electrophorus varii, in the Brazilian Amazon, is described based on morphological and molecular characterization. Ancyracanthus electrophori n. sp. differs from the two congeners namely, Ancyracanthus pinnatifidus and Ancyracanthus schubarti, based on the structure of cephalic appendages, number and arrangement of caudal papillae in males, vulva very close to anus in females, eggs with smoothly mamillated shell, host taxon and geographical origin. Moreover, the new species is the first in the genus to be described with thorny cuticular rings and to be observed with the use of scanning electron microscopy (SEM). The morphology of A. pinnatifidus and A. schubarti is still poorly-known and should be revised in details; however, the separation between them and the new species was clear. Genetic characterization based on 28S rDNA and cytochrome c oxidase subunit I (cox1) mtDNA partial sequences, performed for the first time in Acyracanthus, along with phylogenetic reconstructions using both genetic markers, placed Ancyracanthus electrophori n. sp. in a suggestive basal position within Gnathostomatidae. Phylogenetic reconstructions using cox1 sequences also suggested lack of monophyly in the genera Gnathostoma and Spiroxys and, consequently, in the subfamilies Gnathostominae and Spiroxyinae. However, such results are preliminary. With the first genetic characterization and observations using SEM in Ancyracanthus, resulting in the discovery of a new species and in the expansion of the geographical occurrence of the genus to Amazonian fish, an important step towards a better understanding of these nematodes has been taken.


Asunto(s)
Gymnotiformes , Nematodos , Parásitos , Espirúridos , Femenino , Masculino , Animales , Electrophorus , Filogenia , Brasil
20.
Eur J Prosthodont Restor Dent ; 31(4): 398-406, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37382338

RESUMEN

INTRODUCTION: Adjustments with diamond burs on the ceramic surface can affect its roughness and decrease flexural strength. This study evaluated the effect of polishing or glazing on the surface roughness and biaxial flexural strength of a zirconia-reinforced lithium silicate glass-ceramic upon adjustment with diamond burs. METHODS: Seventy disks were prepared according to ISO 6872 and divided into seven groups (n = 10) according to different adjustments and finishing processes. Surface roughness was measured prior to biaxial flexural strength testing. The topography was analyzed using an atomic force microscope , fracture markings were identified using a stereomicroscope and representative specimens were analyzed using scanning electron microscopy. RESULTS: The use of diamond burs significantly increased the surface roughness and decreased the strength of the evaluated ceramic (p⟨0.05). Polishing reduced the ceramic's roughness but resulted in flexural strength similar to that of the groups with wear (p⟩0.05). The glaze-treated specimens showed flexural strength statistically similar to the control group (p>0.05) but higher roughness, similar to those with wear. CONCLUSIONS: Polishing reduced the surface roughness but did not affect the biaxial flexural strength of the ZLS ceramic. At the same time, the application of glaze after wear increased the strength.


Asunto(s)
Cerámica , Pulido Dental , Ensayo de Materiales , Propiedades de Superficie , Pulido Dental/métodos , Circonio , Diamante , Porcelana Dental
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