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1.
Phys Chem Chem Phys ; 26(28): 19369-19379, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38967480

RESUMO

Quantum spin liquids (QSLs) have become prominent materials of interest in the pursuit of fault-tolerant materials for quantum computing applications. This is due to the fact that these materials are theorized to host an interesting variety of quantum phenomena such as quasi-particles that may behave as anyons as a result of the high entangled nature of the spin states within the systems. Computing the electronic and magnetic properties of these materials is necessary in order to understand the underlying interactions of the materials. In this paper, the structural, electronic, and magnetic properties including lattice parameters, bandgap, Heisenberg coupling constants, and Curie temperatures for α-RuCl3, a promising candidate for the Kitaev QSL model, are computed using periodic density functional theory. Furthermore, various parameters of the calculations (i.e. functional choice, basis set, k-point density, and Hubbard correction) are varied in order to determine what effect, if any, the computational setup has on the computed properties. The results of this study indicate that PBE functional with Hubbard corrections of 1.5-2.5 eV with a k-point density of 3.0 points per Å-1 appear to be the best parameters to compute Heisenberg coupling constants for α-RuCl3. These parameters with the addition of spin orbit coupling works well for computing Curie temperatures for α-RuCl3. Distinct differences are noted in the computations of the bulk structure vs. monolayer structures, indicating that interactions between the layers play a role in the material properties and changes to the inter-layer spacing may result in interesting and unique magnetic properties that require further investigation.

2.
Plast Reconstr Surg Glob Open ; 12(7): e5952, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38957726

RESUMO

Background: Lipedema is the progressive symmetrical deposition of subcutaneous fat and fluid in the lower body, ordinarily sparing the trunk, upper limbs, face, and neck. It may follow an autosomal dominant inheritance pattern. The gold standard treatment for lipedema is complete decongestive therapy, consisting of manual lymphatic drainage and compression garments. This scoping review assessed the existing literature on the effectiveness of liposuction as an alternative treatment for lipedema. Methods: A scoping review of electronically available literature within PubMed, Scopus, and Cochrane focused on liposuction as a treatment for lipedema considering the following inclusion criteria: human studies, case series of 10 or more, controlled trials, randomized controlled trials, patient-reported outcome measurement studies, survey analyses, descriptive studies, retrospective analyses, recurrence included, follow-up of 6 months or more, age 18 years or older, and treatment modality being liposuction. Results: Thirteen studies were selected. Nine studies reported decreased compression therapy use among patients following liposuction. No studies reported a long-term increase in compression therapy following liposuction. Studies found self-reported improvements in pain, mobility, bruising, and overall quality of life for patients following liposuction, many of whom had previously been on compressive therapy. Studies reported low rates of serious adverse events following liposuction, including deep vein thrombosis, pulmonary embolism, and infection. Conclusions: These results suggest that liposuction can be a viable treatment alternative to compression therapy for lipedema in patients whose compression therapy has not been helpful. However, there is not enough evidence to say whether liposuction is as effective as compression for patients first presenting with lipedema.

3.
Chem Biol Drug Des ; 104(1): e14581, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38997237

RESUMO

N-heterocyclic compounds are important molecular scaffolds in the search for new drugs, since most drugs contain heterocyclic moieties in their molecular structure, and some of these classes of heterocycles are able to provide ligands for two or more biological targets. Ketene dithioacetals are important building blocks in organic synthesis and are widely used in the synthesis of N-heterocyclic compounds. In this work, we used double vinylic substitution reactions on ketene dithioacetals to synthesize a small library of heterocyclic derivatives and evaluated their cytotoxic activity in breast and ovarian cancer cells, identifying two benzoxazoles with good potency and selectivity. In silico predictions indicate that the two most active derivatives exhibit physicochemical properties within the range of drug-like compounds and showed potential to interact with HDAC8 and ERK1 cancer-related targets.


Assuntos
Antineoplásicos , Etilenos , Compostos Heterocíclicos , Cetonas , Humanos , Linhagem Celular Tumoral , Etilenos/química , Etilenos/farmacologia , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Cetonas/química , Cetonas/farmacologia , Cetonas/síntese química , Relação Estrutura-Atividade , Histona Desacetilases/metabolismo , Simulação de Acoplamento Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Acetais/química , Acetais/farmacologia , Acetais/síntese química , Proteínas Repressoras
4.
Theriogenology ; 227: 21-30, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38996526

RESUMO

Poor sperm quality in cooled-shipped semen has been related to subpar fertility in horses. Therefore, this study aimed to evaluate the ability of post-cooling sperm processing to improve sperm parameters of cooled-stored stallion semen for artificial insemination. For all experiments, ejaculates were collected, processed, and diluted in skimmed milk-based (SM) medium and stored at 5 °C/24h. In all experiments an aliquot of unprocessed cooled semen was used as a control. In the first experiment (Exp 1.), cooled-stored semen from 16 stallions (n = 32) was processed by SpermFilter or centrifugation (600×g/10min) and resuspended in an egg yolk-based freezing medium containing permeating cryoprotectants (EY-C) for cryopreservation. Sperm recovery and motility parameters were immediately assessed after sperm resuspension in both groups and compared with unprocessed (Unp) samples. In Exp 2., cooled semen samples from six stallions (n = 18) were processed using SpermFilter and resuspended in SM or EY-C. Motility parameters and plasma membrane integrity were assessed in all groups (Unp, SM, and EY-C). In Exp 3, cooled semen from four stallions (n = 20) was processed by SpermFilter, resuspended in SM, EY-C, or egg yolk-based medium without cryoprotectants (EY-nC); and submitted to a thermoresistance test (37 °C/3h). Motility parameters, plasma membrane integrity and stability, mitochondrial membrane potential, mitochondrial superoxide generation, and DNA fragmentation index were evaluated in all groups. Finally, in Exp 4, 39 estrous cycles of 11 mares were inseminated with unprocessed (n = 6) cooled-stored semen or semen cooled at 5 °C/24h and then processed by SpermFilter and resuspended in SM (n = 5), EY-C (n = 11), EY-nC (n = 11), or centrifuged and resuspended in EY-C (n = 6). Overall, semen processing and resuspension in EY mediums (EY-C and EY-nC) improved sperm parameters compared with those of unprocessed semen (P < 0.05). Centrifugation (91 ± 5 %) recovered more sperm than SpermFilter (84 ± 9 %; P < 0.05). Sperm resuspended in EY-nC maintained better sperm parameters throughout the thermoresistance test than those in the other groups (P < 0.05). The fertility rates were similar between all groups (P > 0.05). In conclusion, processing and resuspension in EY medium can improve sperm parameters in post-cooled-stored stallion semen.

5.
Assessment ; : 10731911241259560, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39054862

RESUMO

The UPPS-P Impulsive Behavior Model and the various psychometric instruments developed and validated based on this model are well established in clinical and research settings. However, evidence regarding the psychometric validity, reliability, and equivalence across multiple countries of residence, languages, or gender identities, including gender-diverse individuals, is lacking to date. Using data from the International Sex Survey (N = 82,243), confirmatory factor analyses and measurement invariance analyses were performed on the preestablished five-factor structure of the 20-item short version of the UPPS-P Impulsive Behavior Scale to examine whether (a) psychometric validity and reliability and (b) psychometric equivalence hold across 34 country-of-residence-related, 22 language-related, and three gender-identity-related groups. The results of the present study extend the latter psychometric instrument's well-established relevance to 26 countries, 13 languages, and three gender identities. Most notably, psychometric validity and reliability were evidenced across nine novel translations included in the present study (i.e., Croatian, English, German, Hebrew, Korean, Macedonian, Polish, Portuguese-Portugal, and Spanish-Latin American) and psychometric equivalence was evidenced across all three gender identities included in the present study (i.e., women, men, and gender-diverse individuals).

6.
J Funct Biomater ; 15(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38921522

RESUMO

OBJECTIVES: This study investigated a novel strategy for improving regenerative cartilage outcomes. It combines fractional laser treatment with the implantation of neocartilage generated from autologous dynamic Self-Regenerating Cartilage (dSRC). METHODS: dSRC was generated in vitro from harvested autologous swine chondrocytes. Culture was performed for 2, 4, 8, 10, and 12 weeks to study matrix maturation. Matrix formation and implant integration were also studied in vitro in swine cartilage discs using dSRC or cultured chondrocytes injected into CO2 laser-ablated or mechanically punched holes. Cartilage discs were cultured for up to 8 weeks, harvested, and evaluated histologically and immunohistochemically. RESULTS: The dSRC matrix was injectable by week 2, and matrices grew larger and more solid with time, generating a contiguous neocartilage matrix by week 8. Hypercellular density in dSRC at week 2 decreased over time and approached that of native cartilage by week 8. All dSRC groups exhibited high glycosaminoglycan (GAG) production, and immunohistochemical staining confirmed that the matrix was typical of normal hyaline cartilage, being rich in collagen type II. After 8 weeks in cartilage lesions in vitro, dSRC constructs generated a contiguous cartilage matrix, while isolated cultured chondrocytes exhibited only a sparse pericellular matrix. dSRC-treated lesions exhibited high GAG production compared to those treated with isolated chondrocytes. CONCLUSIONS: Isolated dSRC exhibits hyaline cartilage formation, matures over time, and generates contiguous articular cartilage matrix in fractional laser-created microenvironments in vitro, being well integrated with native cartilage.

7.
J Sex Res ; : 1-16, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905162

RESUMO

Motivations for pornography use may vary across gender identities, sexual orientations, and geographical regions, warranting examination to promote individual and public health. The aims of this study were to validate the Pornography Use Motivations Scale (PUMS) in a diverse, multicultural sample, and develop a short form (PUMS-8) that can assess a wide range of pornography use motivations. Using data from 42 countries (N = 75,117; Mage = 32.07; SDage = 12.37), enabled us to thoroughly evaluate the dimensionality, validity, and reliability of the Pornography Use Motivations Scale (PUMS), leading to the development of the more concise PUMS-8 short scale. Additionally, language-, nationality-, gender-, and sexual-orientation-based measurement invariance tests were conducted to test the comparability across groups. Both the PUMS and the PUMS-8 assess eight pornography use motivations, and both demonstrated excellent psychometric properties. Sexual Pleasure emerged as the most frequent motivation for pornography use across countries, genders, and sexual orientations, while differences were observed concerning other motivations (e.g. self-exploration was more prevalent among gender-diverse individuals than men or women). The motivational background of pornography use showed high similarity in the examined countries. Both the PUMS and the PUMS-8 are reliable and valid measurement tools to assess different types of motivations for pornography use across countries, genders, and sexual orientations. Both scales are recommended for use in research and clinical settings.

8.
Microbes Infect ; : 105378, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880233

RESUMO

Antibody-dependent enhancement (ADE) of dengue virus (DENV) infection is one of the mechanisms contributing to increased severity during heterotypic, secondary infection. The complement protein C1q has been shown to reduce the magnitude of ADE in vitro. Therefore, we investigated the mechanisms of C1q modulation of ADE, focusing on processes of viral entry. Using a model of ADE of DENV-1 infection in human myeloid cell lines in the presence of monoclonal antibodies, 4G2 and 2H2, we found that C1q produced nearly a 40-fold reduction of ADE of DENV-1 in K562 cells, but had no effect in U937 cells. In K562 cells, C1q reduced adsorption of DENV-1/4G2 and exerted a dual inhibitory effect on adsorption and internalization of DENV-1/2H2. Distinct endocytic pathways in the presence of antibody corresponded to conditions where C1q produced a differential action. Also, C1q did not affect the intrinsic cell response mediated by FcγR in human myeloid cells. The modulation of ADE of DENV-1 by C1q is dependent on the FcγR expressed on immune cells and the specificity of the antibody comprising the immune complex. Understanding protective and pathogenic mechanisms in the humoral response to DENV infections is crucial for the successful design of antivirals and vaccines.

10.
Nat Cancer ; 5(7): 1045-1062, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38831058

RESUMO

Tumor progression is accompanied by fibrosis, a condition of excessive extracellular matrix accumulation, which is associated with diminished antitumor immune infiltration. Here we demonstrate that tumor-associated macrophages (TAMs) respond to the stiffened fibrotic tumor microenvironment (TME) by initiating a collagen biosynthesis program directed by transforming growth factor-ß. A collateral effect of this programming is an untenable metabolic milieu for productive CD8+ T cell antitumor responses, as collagen-synthesizing macrophages consume environmental arginine, synthesize proline and secrete ornithine that compromises CD8+ T cell function in female breast cancer. Thus, a stiff and fibrotic TME may impede antitumor immunity not only by direct physical exclusion of CD8+ T cells but also through secondary effects of a mechano-metabolic programming of TAMs, which creates an inhospitable metabolic milieu for CD8+ T cells to respond to anticancer immunotherapies.


Assuntos
Neoplasias da Mama , Linfócitos T CD8-Positivos , Colágeno , Microambiente Tumoral , Macrófagos Associados a Tumor , Microambiente Tumoral/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Feminino , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Colágeno/metabolismo , Animais , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Humanos , Camundongos , Fator de Crescimento Transformador beta/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Reprogramação Metabólica
11.
Int J Clin Health Psychol ; 24(2): 100461, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706570

RESUMO

Background: The three-item Sexual Distress Scale (SDS-3) has been frequently used to assess distress related to sexuality in public health surveys and research on sexual wellbeing. However, its psychometric properties and measurement invariance across cultural, gender and sexual subgroups have not yet been examined. This multinational study aimed to validate the SDS-3 and test its psychometric properties, including measurement invariance across language, country, gender identity, and sexual orientation groups. Methods: We used global survey data from 82,243 individuals (Mean age=32.39 years; 40.3 % men, 57.0 % women, 2.8 % non-binary, and 0.6 % other genders) participating in the International Sexual Survey (ISS; https://internationalsexsurvey.org/) across 42 countries and 26 languages. Participants completed the SDS-3, as well as questions regarding sociodemographic characteristics, including gender identity and sexual orientation. Results: Confirmatory factor analysis (CFA) supported a unidimensional factor structure for the SDS-3, and multi-group CFA (MGCFA) suggested that this factor structure was invariant across countries, languages, gender identities, and sexual orientations. Cronbach's α for the unidimensional score was 0.83 (range between 0.76 and 0.89), and McDonald's ω was 0.84 (range between 0.76 and 0.90). Participants who did not experience sexual problems had significantly lower SDS-3 total scores (M = 2.99; SD=2.54) compared to those who reported sexual problems (M = 5.60; SD=3.00), with a large effect size (Cohen's d = 1.01 [95 % CI=-1.03, -0.98]; p < 0.001). Conclusion: The SDS-3 has a unidimensional factor structure and appears to be valid and reliable for measuring sexual distress among individuals from different countries, gender identities, and sexual orientations.

12.
Sci Rep ; 14(1): 10572, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719916

RESUMO

From over-exploitation of resources to urban pollution, sustaining well-being requires solving social dilemmas of cooperation. Often such dilemmas are studied assuming that individuals occupy fixed positions in a network or lattice. In spatial settings, however, agents can move, and such movements involve costs. Here we investigate how mobility costs impact cooperation dynamics. To this end, we study cooperation dilemmas where individuals are located in a two-dimensional space and can be of two types: cooperators-or cleaners, who pay an individual cost to have a positive impact on their neighbours-and defectors-or polluters, free-riding on others' effort to sustain a clean environment. Importantly, agents can pay a cost to move to a cleaner site. Both analytically and through agent-based simulations we find that, in general, introducing mobility costs increases pollution felt in the limit of fast movement (equivalently slow strategy revision). The effect on cooperation of increasing mobility costs is non-monotonic when mobility co-occurs with strategy revision. In such scenarios, low (yet non-zero) mobility costs minimise cooperation in low density environments; whereas high costs can promote cooperation even when a minority of agents initially defect. Finally, we find that heterogeneity in mobility cost affects the final distribution of strategies, leading to differences in who supports the burden of having a clean environment.


Assuntos
Comportamento Cooperativo , Humanos , Teoria dos Jogos , Modelos Teóricos , Seguridade Social/economia
13.
Eur Spine J ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717495

RESUMO

PURPOSE: To conduct an independent assessment of inter- and intraobserver agreement for the META score as a tool for differentiating osteoporotic vertebral fractures and multiple myeloma vertebral fractures. METHODS: This is a retrospective observational study. The magnetic resonance imaging analysis was made by two independent spinal surgeons. We designated a Subjective assessment, in which the surgeon should establish a diagnostic classification for each vertebral fracture based on personal experience: secondary to osteoporosis, categorized as a benign vertebral fracture (BVF), or attributed to multiple myeloma, categorized a malign vertebral fracture (MVF). After a 90-day interval, both surgeons repeated the evaluations. For the next step, the observers should establish a diagnosis between BVF and MVF according to the META score system, and both observers repeated the evaluations after a 90-day interval. The intra and interobserver reliability of the Subjective evaluation was studied using the kappa (κ) test. Then, the META evaluations were paralleled using the intraclass correlation coefficient (ICC). RESULTS: A total of 220 patients who had the potential to participate in the study were initially enrolled, but after applying the exclusion criteria, 44 patients were included. Thirty-three patients had BVF, and 12 patients presented MVF. Interobserver agreement for both Subjective evaluations moments (initial and 90-days interval) found a slight agreement for both moments (0.35 and 0.40 respectively). Kappa test for both META evaluations moments (initial and 90-days interval) found a moderate interobserver agreement for both moments (0.54 and 0.48 respectively). It was observed that the ICC calculated for the Initial evaluation using META score was 0.680 and that in the 90-days interval was 0.726, indicating regular to good agreement. Kappa test for intraobserver agreements for the Subjective evaluation presented moderate agreement for both Surgeons. On the other side, Kappa test for intraobserver agreements for the META evaluation presented substantial agreement for both Surgeons. The Intraclass Correlation Coefficient of the META score found presented an almost perfect agreement for both Surgeons. CONCLUSION: Intra and interobserver agreement for both surgeons were unsatisfactory. The lack of consistent reproducibility by the same observer discourages and disfavors the routine use of the META score in clinical decision making, when potentially cases of multiple myeloma may be present.

14.
J Hypertens ; 42(6): 1101-1104, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690908

RESUMO

Isolated nocturnal hypertension (INHT), defined as nighttime elevated blood pressure (BP) with normal daytime BP assessed by ambulatory BP monitoring, is associated with higher cardiovascular morbidity and mortality. We hypothesized that an alteration in the circulating renin-angiotensin system (RAS) contributes to INHT development. We examined circulating levels of angiotensin (Ang) (1-7) and Ang II and ACE2 activity in 26 patients that met the INHT criteria, out of 50 that were referred for BP evaluation (62% women, 45 ±â€Š16 years old). Those with INHT were older, had a higher BMI, lower circulating Ang-(1-7) (P = 0.002) and Ang II levels (P = 0.02) and no change in ACE2 activity compared to those normotensives. Nighttime DBP was significantly correlated with Ang-(1-7) and Ang II levels. Logistic regression showed significant association in Ang-(1-7) and Ang II levels with INHT. Our study reveals differences in circulating RAS in individuals with INHT.


Assuntos
Angiotensina II , Angiotensina I , Hipertensão , Fragmentos de Peptídeos , Humanos , Angiotensina I/sangue , Feminino , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Hipertensão/sangue , Hipertensão/fisiopatologia , Adulto , Angiotensina II/sangue , Sistema Renina-Angiotensina/fisiologia , Ritmo Circadiano , Pressão Sanguínea , Enzima de Conversão de Angiotensina 2/sangue , Monitorização Ambulatorial da Pressão Arterial , Peptidil Dipeptidase A/sangue
16.
J Oral Rehabil ; 51(8): 1521-1529, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38717007

RESUMO

BACKGROUND: Current clinical approaches to regenerate temporomandibular joint (TMJ) articulating cartilage defects only treat the symptoms (i.e. pain and dysfunction) and do not seek to restore joint integrity for long-term relief. Therefore, we investigated a novel self-assembling tissue-engineered cartilage to overcome this significant clinical issue for TMJ regenerative purposes. OBJECTIVES: Examine the maturation of dynamic self-regenerating cartilage (dSRC) using auricular chondrocytes and evaluate a novel combinatorial approach with fractional laser treatment and dSRC implantation for TMJ cartilage repair. MATERIALS AND METHODS: A suspension of 107 freshly harvested rabbit ear chondrocytes was cultured under a continuous reciprocating motion to form the dSRC. After 2, 4 and 8 weeks of culture, dSRC samples were stained with H&E, Safranin-O and Toluidine Blue. Immunohistochemistry (IHC) was performed for collagens type I and II. Channels (300-500 µm diameter and 1.2-1.5 mm depth) were created in six freshly harvested condyles using a fractional Erbium laser. Two groups were tested: dSRC in a laser-ablated lesion (experimental) and an empty laser-ablated channel (control). TMJ condyles were cultured for up to 8 weeks and analysed as described above. RESULTS: H&E staining showed a high cell density in dSRC compared to native cartilage. All dSRC groups demonstrated intense Safranin-O staining, indicating high glycosaminoglycan (GAG) production and intense Toluidine Blue staining showed high proteoglycan content. IHC confirmed that dSRC consisted predominantly of collagen type II. The experimental group showed improved cartilage repair at both time points compared to the empty channels. CONCLUSION: dSRC viability and successful matrix formation were demonstrated in vitro. The combination of fractional laser ablation and dSRC implantation enhanced cartilage repair.


Assuntos
Cartilagem Articular , Condrócitos , Regeneração , Articulação Temporomandibular , Engenharia Tecidual , Animais , Coelhos , Condrócitos/transplante , Engenharia Tecidual/métodos , Articulação Temporomandibular/cirurgia , Articulação Temporomandibular/patologia , Regeneração/fisiologia , Cartilagem Articular/cirurgia , Cartilagem Articular/patologia , Transtornos da Articulação Temporomandibular/cirurgia , Transtornos da Articulação Temporomandibular/fisiopatologia , Transtornos da Articulação Temporomandibular/terapia , Células Cultivadas , Cartilagem da Orelha/fisiologia , Técnicas In Vitro
18.
Angew Chem Int Ed Engl ; 63(26): e202406663, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38655628

RESUMO

A pair of enantiopure [6]-azairidahelicenes incorporating chirality at the metal center and on the helicenic ligand were synthesized by dynamic kinetic resolution (dkr) of a configurationally labile [4]-helicenic ligand (4-(2-pyridyl)-benzo[g]phenanthrene, L1H) using bis-cyclometalated chiral-at-metal only iridium(III) precursors as chiral inductors. The origin of the observed dkr is attributed to the different conformation and stability of diastereomeric reaction intermediates formed during the cyclometalation process. The isolated enantiomers exhibited circularly polarized phosphorescence (CPP), with |gphos| values of 1.8×10-3.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38643455

RESUMO

Estrone (E1) constitutes the primary component in oral conjugated equine estrogens (CEEs) and serves as the principal estrogen precursor in the female circulation in the post-menopause. E1 induces endothelium-dependent vasodilation and activate PI3K/NO/cGMP signaling. To assess whether E1 mitigates vascular dysfunction associated with postmenopause and explore the underlying mechanisms, we examined the vascular effects of E1 in ovariectomized (OVX) rats, a postmenopausal experimental model. Blood pressure was measured using tail-cuff plethysmography, and aortic rings were isolated to assess responses to phenylephrine, acetylcholine (ACh), and sodium nitroprusside. Responses to ACh in rings pre-incubated with superoxide dismutase (SOD), catalase (CAT), or apocynin were also evaluated. Protein expression of SOD, CAT, NOX1, NOX2, and NOX4 was determined by Western blotting. E1 treatment resulted in decreased body weight and retroperitoneal fat, increased uterine weight, and prevented elevated blood pressure in the OVX group. Furthermore, E1 improved endothelium-dependent ACh vasodilation, activated compensatory antioxidant mechanisms - i.e. increased SOD and CAT antioxidant enzymes activity, and decreased NOX4 expression. This, in turn, helped prevent oxidative stress and endothelial dysfunction in OVX rats. Additionally, E1 treatment reversed the increased total LDL cholesterol observed in the OVX group. The findings underscore protective effects of E1 on the cardiovascular system, counteracting OVX-related oxidative stress and endothelial dysfunction in Wistar rats. E1 exhibits promising therapeutic benefits for managing cardiovascular health, particularly in postmenopausal conditions.

20.
Sci Total Environ ; 924: 171533, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38458446

RESUMO

Amid growing environmental concerns and the imperative for sustainable agricultural practices, this study examines the potential of nitrogen-fixing cyanobacteria as biofertilizers, particularly in cotton cultivation. The reliance on synthetic nitrogen fertilizers (SNFs), prevalent in modern agriculture, poses significant environmental challenges, including greenhouse gas emissions and water system contamination. This research aims to shift this paradigm by exploring the capacity of cyanobacteria as a natural and sustainable alternative. Utilizing advanced metabarcoding methods to analyze the 16S rRNA gene, we conducted a comprehensive assessment of soil bacterial communities within cotton fields. This study focused on evaluating the diversity, structure, taxonomic composition, and potential functional characteristics of these communities. Emphasis was placed on the isolation of native N2-fixing cyanobacteria strains rom cotton soils, and their subsequent effects on cotton growth. Results from our study demonstrate significant plant growth-promoting (PGP) activities, measured as N2 fixation, production of Phytohormones, Fe solubilization and biofertilization potential of five isolated cyanobacterial strains, underscoring their efficacy in cotton. These findings suggest a viable pathway for replacing chemical-synthetic nitrogen fertilizers with natural, organic alternatives. The reintegration of these beneficial species into agricultural ecosystems can enhance crop growth while fostering a balanced microbial environment, thus contributing to the broader goals of global sustainable agriculture.


Assuntos
Cianobactérias , Ecossistema , Nitrogênio , Fertilizantes , RNA Ribossômico 16S , Agricultura , Solo , Gossypium
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