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1.
Nature ; 622(7981): 48-52, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37619607

RESUMO

The formation of stars and planets is accompanied not only by the build-up of matter, namely accretion, but also by its expulsion in the form of highly supersonic jets that can stretch for several parsecs1,2. As accretion and jet activity are correlated and because young stars acquire most of their mass rapidly early on, the most powerful jets are associated with the youngest protostars3. This period, however, coincides with the time when the protostar and its surroundings are hidden behind many magnitudes of visual extinction. Millimetre interferometers can probe this stage but only for the coolest components3. No information is provided on the hottest (greater than 1,000 K) constituents of the jet, that is, the atomic, ionized and high-temperature molecular gases that are thought to make up the jet's backbone. Detecting such a spine relies on observing in the infrared that can penetrate through the shroud of dust. Here we report near-infrared observations of Herbig-Haro 211 from the James Webb Space Telescope, an outflow from an analogue of our Sun when it was, at most, a few times 104 years old. These observations reveal copious emission from hot molecules, explaining the origin of the 'green fuzzies'4-7 discovered nearly two decades ago by the Spitzer Space Telescope8. This outflow is found to be propagating slowly in comparison to its more evolved counterparts and, surprisingly, almost no trace of atomic or ionized emission is seen, suggesting its spine is almost purely molecular.

2.
J Am Chem Soc ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39350717

RESUMO

The development of next generation soft and recyclable materials prominently features dynamic (reversible) chemistries such as host-guest, supramolecular, and dynamic covalent. Dynamic systems enable injectability, reprocessability, and time-dependent mechanical properties. These properties arise from the inherent relationship between the rate and equilibrium constants (RECs) of molecular junctions (cross-links) and the resulting macroscopic behavior of dynamic networks. However, few examples explicitly measure RECs while exploring this connection between molecular and material properties, particularly for polymeric hydrogel systems. Here we use dynamic covalent imine formation to study how single-point compositional changes in NH2-terminated nucleophiles affect binding constants and resulting hydrogel mechanical properties. We explored both model small molecule studies and model polymeric macromers, and found >3-decade change in RECs. Leveraging established relationships in the literature, we then developed a simple model to describe the cross-linking equilibrium and predict changes in hydrogel mechanical properties. Interestingly, we observed that a narrow ≈2-decade range of Keq's determine the bound fraction of imines. Our model allowed us to uncover a regime where adding cross-linker before saturation can decrease the cross-link density of a hydrogel. We then demonstrated the veracity of this predicted behavior experimentally. Notably this emergent behavior is not accounted for in covalent hydrogel theory. This study expands upon structure-reactivity relationships for imine formation, highlighting how quantitative determination of RECs facilitates predicting macroscopic behavior. Furthermore, while the present study focuses on dynamic covalent imine formation, the underlying principles of this work are applicable to the general bottom-up design of soft and recyclable dynamic materials.

3.
J Am Chem Soc ; 146(35): 24330-24347, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39163519

RESUMO

Dynamic hydrogels are attractive platforms for tissue engineering and regenerative medicine due to their ability to mimic key extracellular matrix (ECM) mechanical properties like strain-stiffening and stress relaxation while enabling enhanced processing characteristics like injectability, 3D printing, and self-healing. Systems based on imine-type dynamic covalent chemistry (DCvC) have become increasingly popular. However, most reported polymers comprising aldehyde groups are based on either end-group-modified synthetic or side-chain-modified natural polymers; synthetic versions of side-chain-modified polymers are noticeably absent. To facilitate access to new classes of dynamic hydrogels, we report the straightforward synthesis of a water-soluble copolymer with a tunable fraction of pendant aldehyde groups (12-64%) using controlled radical polymerization and their formation into hydrogel biomaterials with dynamic cross-links. We found the polymer synthesis to be well-controlled with the determined reactivity ratios consistent with a blocky gradient microarchitecture. Subsequently, we observed fast gelation kinetics with imine-type cross-linking. We were able to vary hydrogel stiffness from ≈2 to 20 kPa, tune the onset of strain-stiffening toward a biologically relevant regime (σc ≈ 10 Pa), and demonstrate cytocompatibility using human dermal fibroblasts. Moreover, to begin to mimic the dynamic biochemical nature of the native ECM, we highlight the potential for temporal modulation of ligands in our system to demonstrate ligand displacement along the copolymer backbone via competitive binding. The combination of highly tunable composition, stiffness, and strain-stiffening, in conjunction with spatiotemporal control of functionality, positions these cytocompatible copolymers as a powerful platform for the rational design of next-generation synthetic biomaterials.


Assuntos
Aldeídos , Materiais Biocompatíveis , Hidrogéis , Polímeros , Hidrogéis/química , Hidrogéis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Ligantes , Aldeídos/química , Polímeros/química , Polímeros/síntese química , Humanos
4.
Am J Physiol Heart Circ Physiol ; 326(1): H203-H215, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37975708

RESUMO

Ventricular arrhythmias contribute significantly to cardiovascular mortality, with coronary artery disease as the predominant underlying cause. Understanding the mechanisms of arrhythmogenesis is essential to identify proarrhythmic factors and develop novel approaches for antiarrhythmic prophylaxis and treatment. Animal models are vital in basic research on cardiac arrhythmias, encompassing molecular, cellular, ex vivo whole heart, and in vivo models. Most studies use either in vivo protocols lacking important information on clinical relevance or exclusively ex vivo protocols, thereby missing the opportunity to explore underlying mechanisms. Consequently, interpretation may be difficult due to dissimilarities in animal models, interventions, and individual properties across animals. Moreover, proarrhythmic effects observed in vivo are often not replicated in corresponding ex vivo preparations during mechanistic studies. We have established a protocol to perform both an in vivo and ex vivo electrophysiological characterization in an arrhythmogenic rat model with heart failure following myocardial infarction. The same animal is followed throughout the experiment. In vivo methods involve intracardiac programmed electrical stimulation and external defibrillation to terminate sustained ventricular arrhythmia. Ex vivo methods conducted on the Langendorff-perfused heart include an electrophysiological study with optical mapping of regional action potentials, conduction velocities, and dispersion of electrophysiological properties. By exploring the retention of the in vivo proarrhythmic phenotype ex vivo, we aim to examine whether the subsequent ex vivo detailed measurements are relevant to in vivo pathological behavior. This protocol can enhance greater understanding of cardiac arrhythmias by providing a standardized, yet adaptable model for evaluating arrhythmogenicity or antiarrhythmic interventions in cardiac diseases.NEW & NOTEWORTHY Rodent models are widely used in arrhythmia research. However, most studies do not standardize clinically relevant in vivo and ex vivo techniques to support their conclusions. Here, we present a comprehensive electrophysiological protocol in an arrhythmogenic rat model, connecting in vivo and ex vivo programmed electrical stimulation with optical mapping. By establishing this protocol, we aim to facilitate the adoption of a standardized model for investigating arrhythmias, enhancing research rigor and comparability in this field.


Assuntos
Arritmias Cardíacas , Infarto do Miocárdio , Ratos , Animais , Coração/fisiologia , Antiarrítmicos/farmacologia , Antiarrítmicos/uso terapêutico , Modelos Animais
5.
BMC Plant Biol ; 24(1): 769, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39135189

RESUMO

BACKGROUND: Japanese knotweed (Reynoutria japonica var. japonica), a problematic invasive species, has a wide geographical distribution. We have previously shown the potential for attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and chemometrics to segregate regional differentiation between Japanese knotweed plants. However, the contribution of environment to spectral differences remains unclear. Herein, the response of Japanese knotweed to varied environmental habitats has been studied. Eight unique growth environments were created by manipulation of the red: far-red light ratio (R: FR), water availability, nitrogen, and micronutrients. Their impacts on plant growth, photosynthetic parameters, and ATR-FTIR spectral profiles, were explored using chemometric techniques, including principal component analysis (PCA), linear discriminant analysis, support vector machines (SVM) and partial least squares regression. Key wavenumbers responsible for spectral differences were identified with PCA loadings, and molecular biomarkers were assigned. Partial least squared regression (PLSR) of spectral absorbance and root water potential (RWP) data was used to create a predictive model for RWP. RESULTS: Spectra from plants grown in different environments were differentiated using ATR-FTIR spectroscopy coupled with SVM. Biomarkers highlighted through PCA loadings corresponded to several molecules, most commonly cell wall carbohydrates, suggesting that these wavenumbers could be consistent indicators of plant stress across species. R: FR most affected the ATR-FTIR spectra of intact dried leaf material. PLSR prediction of root water potential achieved an R2 of 0.8, supporting the potential use of ATR-FTIR spectrometers as sensors for prediction of plant physiological parameters. CONCLUSIONS: Japanese knotweed exhibits environmentally induced phenotypes, indicated by measurable differences in their ATR-FTIR spectra. This high environmental plasticity reflected by key biomolecular changes may contribute to its success as an invasive species. Light quality (R: FR) appears critical in defining the growth and spectral response to environment. Cross-species conservation of biomarkers suggest that they could function as indicators of plant-environment interactions including abiotic stress responses and plant health.


Assuntos
Fenótipo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Componente Principal , Espécies Introduzidas , Folhas de Planta/química , Fotossíntese
6.
Appl Environ Microbiol ; 90(9): e0029824, 2024 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-39189736

RESUMO

We report the relationship between enrichment of adapted populations and enhancement of community functional resilience in methanogenic bioreactors. Although previous studies have shown the positive effects of acclimation, this work directly investigated the relationships between microbiome dynamics and performance of anaerobic co-digesting reactors in response to different levels of an environmental perturbation (loading of grease interceptor waste [GIW]). Using the methanogenic microbiome from a full-scale digester, we developed eight sets of microbial communities in triplicate using different feed sources. These substrate-specific microbiomes were then exposed to three independent disturbance events of low-, mid- and high-GIW loading rates. This approach allowed us to directly attribute differences in community responses to differences in community composition. Despite identical inocula, environment (digester operation, substrate loading rate, and feeding patterns) and general whole-community function (methane production and effluent quality) during the cultivation period, different substrates led to different microbial community assemblies. Lipid pre-acclimation led to enrichment of a pool of specialized populations, along with thriving of sub-dominant communities. The enrichment of these populations improved functional resilience and process performance when exposed to a low level of lipid-rich perturbation compared with less-acclimated communities. At higher levels of perturbation, the communities were not able to recover methanogenesis, indicating a loading limit to the resilience response. This study extends our current understanding of environmental perturbations, feed-specific adaptation, and functional resilience in methanogenic bioreactors.IMPORTANCEThis study demonstrates, for the first time for GIW co-digestion, how applying similar perturbations to different microbial communities was used to directly identify the causal relationships between microbial community, function, and environment in triplicate anaerobic microbiomes. We evaluated the impact of feed-specific adaptation on methanogenic microbiomes and demonstrated how microbiomes can be influenced to improve their functional (methanogenic) resilience to GIW inhibition. These findings demonstrate how an ecological framework can help improve a biological engineering application, and more specifically, increase the potential of anaerobic co-digestion for converting wastes to energy.


Assuntos
Reatores Biológicos , Metano , Microbiota , Microbiota/fisiologia , Reatores Biológicos/microbiologia , Anaerobiose , Metano/metabolismo , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética
7.
Chemistry ; 30(25): e202400569, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393539

RESUMO

Heterocycles that pair main group elements and nitrogen are extremely important within the π-conjugated heterocycles research community. Compared to the vast number of boron-nitrogen heterocycles, those that include phosphorus are less common. Furthermore, the use of phosphorus-nitrogen triple bonds of any type to prepare such compounds is unprecedented. Here, we pair pyridyl hydrazonide ligands with phosphadiazonium cations and demonstrate that the chelated Mes*NP group is directly implicated in the photophysical and redox properties observed for the resulting heterocycles. In doing so, we introduce a novel building block for the production of phosphorus-containing heterocycles that could find use in small molecule activation and catalysis or as the functional component of emerging organic electronics.

8.
Immunity ; 42(6): 1100-15, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26084025

RESUMO

Tertiary lymphoid organs (TLOs) emerge during nonresolving peripheral inflammation, but their impact on disease progression remains unknown. We have found in aged Apoe(-/-) mice that artery TLOs (ATLOs) controlled highly territorialized aorta T cell responses. ATLOs promoted T cell recruitment, primed CD4(+) T cells, generated CD4(+), CD8(+), T regulatory (Treg) effector and central memory cells, converted naive CD4(+) T cells into induced Treg cells, and presented antigen by an unusual set of dendritic cells and B cells. Meanwhile, vascular smooth muscle cell lymphotoxin ß receptors (VSMC-LTßRs) protected against atherosclerosis by maintaining structure, cellularity, and size of ATLOs though VSMC-LTßRs did not affect secondary lymphoid organs: Atherosclerosis was markedly exacerbated in Apoe(-/-)Ltbr(-/-) and to a similar extent in aged Apoe(-/-)Ltbr(fl/fl)Tagln-cre mice. These data support the conclusion that the immune system employs ATLOs to organize aorta T cell homeostasis during aging and that VSMC-LTßRs participate in atherosclerosis protection via ATLOs.


Assuntos
Envelhecimento/imunologia , Aterosclerose/imunologia , Receptor beta de Linfotoxina/metabolismo , Miócitos de Músculo Liso/fisiologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Túnica Adventícia/imunologia , Envelhecimento/genética , Animais , Aorta/patologia , Apolipoproteínas E/genética , Aterosclerose/genética , Diferenciação Celular/genética , Movimento Celular/genética , Células Cultivadas , Coristoma/imunologia , Memória Imunológica , Ativação Linfocitária/genética , Tecido Linfoide/imunologia , Receptor beta de Linfotoxina/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteínas dos Microfilamentos/genética , Proteínas Musculares/genética
9.
Clin Transplant ; 38(9): e15439, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39190896

RESUMO

BACKGROUND: Living donor kidney transplantation is the optimal treatment for end-stage kidney disease; however, few living donor candidates (LDCs) who begin evaluation actually donate. While some LDCs are deemed medically ineligible, others discontinue for potentially modifiable reasons. METHODS: At five transplant centers, we conducted a prospective cohort study measuring LDCs' clinical and psychosocial characteristics, educational preparation, readiness to donate, and social determinants of health. We followed LDCs for 12 months after evaluation to determine whether they donated a kidney, opted to discontinue, had modifiable reasons for discontinuing, were medically ineligible, or had other recipient-related reasons for discontinuing. RESULTS: Among 2184 LDCs, 18.6% donated, 38.2% opted to or had modifiable reasons for discontinuing, and 43.2% were deemed ineligible due to medical or recipient-related reasons. Multivariable analyses comparing successful LDCs with those who did not complete donation for modifiable reasons (N = 1241) found that LDCs who discussed donation with the recipient before evaluation (OR, 2.31; 95% CI, 1.54-3.46), had completed high school (OR, 2.01; 95% CI, 1.21-3.35), or were a "close relation" to their recipient (OR, 1.89; 95% CI, 1.33-2.69) were more likely to donate. Conversely, LDCs who reported religion as important (OR, 0.55; 95% CI, 0.38-0.80), were Non-White (OR, 0.70; 95% CI, 0.49-1.00), or had overall higher anxiety scores (OR, 0.92; 95% CI, 0.86-0.99) were less likely to donate. CONCLUSION: With fewer than a fifth of LDCs donating, developing programs to provide greater emotional support and facilitate open discussions between LDCs and recipients earlier may increase living donation rates.


Assuntos
Falência Renal Crônica , Transplante de Rim , Doadores Vivos , Humanos , Doadores Vivos/psicologia , Doadores Vivos/provisão & distribuição , Feminino , Masculino , Transplante de Rim/psicologia , Estudos Prospectivos , Pessoa de Meia-Idade , Seguimentos , Prognóstico , Adulto , Falência Renal Crônica/cirurgia , Falência Renal Crônica/psicologia , Obtenção de Tecidos e Órgãos
10.
Analyst ; 149(19): 4851-4861, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39105622

RESUMO

Lung cancer is one of the most commonly occurring malignant tumours worldwide. Although some reference methods such as X-ray, computed tomography or bronchoscope are widely used for clinical diagnosis of lung cancer, there is still a need to develop new methods for early detection of lung cancer. Especially needed are approaches that might be non-invasive and fast with high analytical precision and statistically reliable. Herein, we developed a swab "dip" test in saliva whereby swabs were analysed using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy harnessed to principal component analysis-quadratic discriminant analysis (QDA) and variable selection techniques employing successive projections algorithm (SPA) and genetic algorithm (GA) for feature selection/extraction combined with QDA. A total of 1944 saliva samples (56 designated as lung-cancer positive and 1888 designed as controls) were obtained in a lung cancer-screening programme being undertaken in North-West England. GA-QDA models achieved, for the test set, sensitivity and specificity values of 100.0% and 99.1%, respectively. Three wavenumbers (1422 cm-1, 1546 cm-1 and 1578 cm-1) were identified using the GA-QDA model to distinguish between lung cancer and controls, including ring C-C stretching, CN adenine, Amide II [δ(NH), ν(CN)] and νs(COO-) (polysaccharides, pectin). These findings highlight the potential of using biospectroscopy associated with multivariate classification algorithms to discriminate between benign saliva samples and those with underlying lung cancer.


Assuntos
Neoplasias Pulmonares , Análise de Componente Principal , Saliva , Humanos , Saliva/química , Neoplasias Pulmonares/diagnóstico , Análise Discriminante , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Algoritmos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso
11.
Analyst ; 149(12): 3380-3395, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38712606

RESUMO

Plant hormones are important in the control of physiological and developmental processes including seed germination, senescence, flowering, stomatal aperture, and ultimately the overall growth and yield of plants. Many currently available methods to quantify such growth regulators quickly and accurately require extensive sample purification using complex analytic techniques. Herein we used ultra-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) to create and validate the prediction of hormone concentrations made using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectral profiles of both freeze-dried ground leaf tissue and extracted xylem sap of Japanese knotweed (Reynoutria japonica) plants grown under different environmental conditions. In addition to these predictions made with partial least squares regression, further analysis of spectral data was performed using chemometric techniques, including principal component analysis, linear discriminant analysis, and support vector machines (SVM). Plants grown in different environments had sufficiently different biochemical profiles, including plant hormonal compounds, to allow successful differentiation by ATR-FTIR spectroscopy coupled with SVM. ATR-FTIR spectral biomarkers highlighted a range of biomolecules responsible for the differing spectral signatures between growth environments, such as triacylglycerol, proteins and amino acids, tannins, pectin, polysaccharides such as starch and cellulose, DNA and RNA. Using partial least squares regression, we show the potential for accurate prediction of plant hormone concentrations from ATR-FTIR spectral profiles, calibrated with hormonal data quantified by UHPLC-HRMS. The application of ATR-FTIR spectroscopy and chemometrics offers accurate prediction of hormone concentrations in plant samples, with advantages over existing approaches.


Assuntos
Reguladores de Crescimento de Plantas , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Reguladores de Crescimento de Plantas/análise , Análise dos Mínimos Quadrados , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão/métodos , Máquina de Vetores de Suporte , Espectrometria de Massas/métodos , Análise de Componente Principal
12.
Analyst ; 149(2): 497-506, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38063458

RESUMO

Diabetes mellitus (DM) is a metabolic disease with an increasing prevalence that is causing worldwide concern. The pre-diabetes stage is the only reversible stage in the patho-physiological process towards DM. Due to the limitations of traditional methods, the diagnosis and detection of DM and pre-diabetes are complicated, expensive, and time-consuming. Therefore, it would be of great benefit to develop a simple, rapid and inexpensive diagnostic test. Herein, the infrared (IR) spectra of serum samples from 111 DM patients, 111 pre-diabetes patients and 333 healthy volunteers were collected using attenuated total reflection Fourier-transform IR (ATR-FTIR) spectroscopy and this was combined with the multivariate analysis of principal component analysis linear discriminant analysis (PCA-LDA) to develop a discriminant model to verify the diagnostic potential of this approach. The study found that the accuracy of the test model established by ATR-FTIR spectroscopy combined with PCA-LDA was 97%, and the sensitivity and specificity were 100% and 100% in the control group, 94% and 98% in the pre-diabetes group, and 91% and 98% in the DM group, respectively. This indicates that this method can effectively diagnose DM and pre-diabetes, which has far-reaching clinical significance.


Assuntos
Diabetes Mellitus , Estado Pré-Diabético , Humanos , Estado Pré-Diabético/diagnóstico , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Multivariada , Análise Discriminante , Diabetes Mellitus/diagnóstico , Análise de Componente Principal , Proteínas Mutadas de Ataxia Telangiectasia
13.
AIDS Behav ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39249627

RESUMO

Children who are HIV-exposed and uninfected (CHEU) are at increased risk for poor growth, health, and development compared to children who are HIV-unexposed and uninfected. To support families with CHEU, we assessed the acceptability of engaging family members to support women living with HIV (WLWH) with exclusive breastfeeding (EBF) and antiretroviral therapy (ART) adherence and to engage in responsive infant caregiving. We conducted trials of improved practices, a consultative research approach, that follows participants over time as they try recommended behaviors. We enrolled postpartum women in Lusaka, Zambia, who identified home supporters. At visit 1, WLWH were interviewed about current practices. At visit 2, WLWH and home supporters received tailored EBF, responsive care, and ART adherence counseling. At visit 3, WLWH and home supporters were interviewed about their experiences trying recommended practices for 2-3 weeks. Interview transcripts were analyzed thematically. Participants included 23 WLWH, 15 male partners, and 8 female family members. WLWH reported several barriers to EBF. The most common were fear of HIV transmission via breastfeeding-despite high ART adherence-and insufficient breastmilk. After counseling, WLWH reported less fear of HIV transmission and improved breastfeeding practices. Home supporters reported providing WLWH increased support for EBF and ART adherence and practicing responsive caregiving. Both male and female home supporters appreciated being included in counseling and more involved in caregiving, and WLWH valued the increased support. Families with CHEU need focused support. Tailored counseling and family support for WLWH show promise for improving EBF, responsive caregiving, and ART adherence.

14.
BMC Cardiovasc Disord ; 24(1): 409, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103770

RESUMO

BACKGROUND: This study evaluated the effects of concurrent isolated training (T) or training combined with the antioxidant N-acetylcysteine (NAC) on cardiac remodeling and oxidative stress in spontaneously hypertensive rats (SHR). METHODS: Six-month-old male SHR were divided into sedentary (S, n = 12), concurrent training (T, n = 13), sedentary supplemented with NAC (SNAC, n = 13), and concurrent training with NAC supplementation (TNAC, n = 14) groups. T and TNAC rats were trained three times a week on a treadmill and ladder; NAC supplemented groups received 120 mg/kg/day NAC in rat chow for eight weeks. Myocardial antioxidant enzyme activity and lipid hydroperoxide concentration were assessed by spectrophotometry. Gene expression of NADPH oxidase subunits Nox2, Nox4, p22 phox, and p47 phox was evaluated by real time RT-PCR. Statistical analysis was performed using ANOVA and Bonferroni or Kruskal-Wallis and Dunn. RESULTS: Echocardiogram showed concentric remodeling in TNAC, characterized by increased relative wall thickness (S 0.40 ± 0.04; T 0.39 ± 0.03; SNAC 0.40 ± 0.04; TNAC 0.43 ± 0.04 *; * p < 0.05 vs T and SNAC) and diastolic posterior wall thickness (S 1.50 ± 0.12; T 1.52 ± 0.10; SNAC 1.56 ± 0.12; TNAC 1.62 ± 0.14 * mm; * p < 0.05 vs T), with improved contractile function (posterior wall shortening velocity: S 39.4 ± 5.01; T 36.4 ± 2.96; SNAC 39.7 ± 3.44; TNAC 41.6 ± 3.57 * mm/s; * p < 0.05 vs T). Myocardial lipid hydroperoxide concentration was lower in NAC treated groups (S 210 ± 48; T 182 ± 43; SNAC 159 ± 33 *; TNAC 110 ± 23 *# nmol/g tissue; * p < 0.05 vs S, # p < 0.05 vs T and SNAC). Nox 2 and p22 phox expression was higher and p47 phox lower in T than S [S 1.37 (0.66-1.66); T 0.78 (0.61-1.04) *; SNAC 1.07 (1.01-1.38); TNAC 1.06 (1.01-1.15) arbitrary units; * p < 0.05 vs S]. NADPH oxidase subunits did not differ between TNAC, SNAC, and S groups. CONCLUSION: N-acetylcysteine supplementation alone reduces oxidative stress in untreated spontaneously hypertensive rats. The combination of N-acetylcysteine and concurrent exercise further decreases oxidative stress. However, the lower oxidative stress does not translate into improved cardiac remodeling and function in untreated spontaneously hypertensive rats.


Assuntos
Acetilcisteína , Hipertensão , NADPH Oxidases , Estresse Oxidativo , Ratos Endogâmicos SHR , Remodelação Ventricular , Animais , Masculino , Estresse Oxidativo/efeitos dos fármacos , Acetilcisteína/farmacologia , Remodelação Ventricular/efeitos dos fármacos , Hipertensão/fisiopatologia , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , NADPH Oxidases/metabolismo , NADPH Oxidases/genética , Ratos , Antioxidantes/farmacologia , Condicionamento Físico Animal , Modelos Animais de Doenças , NADPH Oxidase 2/metabolismo , NADPH Oxidase 2/genética , NADPH Oxidase 4/metabolismo , NADPH Oxidase 4/genética , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Miocárdio/metabolismo , Miocárdio/patologia , Peróxidos Lipídicos/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos , Suplementos Nutricionais , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Hipertrofia Ventricular Esquerda/metabolismo
16.
BMC Ophthalmol ; 24(1): 47, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291358

RESUMO

BACKGROUND: Retinoblastoma (rb) is the most frequent intraocular tumor, accounting for 3% of all childhood cancers. Heritable rb survivors are germline carriers for an RB1 mutation and have a lifelong risk to develop non-ocular second primary tumors (SPTs) involving multiple other organs like the bones, soft tissues, or skin. These SPTs usually become manifest several years succeeding the diagnosis of rb. In our instance, however, a non-ocular SPT presented prior to the diagnosis of heritable rb. CASE PRESENTATION: We report a rare case of a monozygotic twin who presented with primary rhabdomyosarcoma (RMS) preceding the manifestation of heritable rb. The rb was diagnosed when the child developed strabismus while already on therapy for the RMS. The child underwent therapy for both as per defined treatment protocols. The rb regressed well on treatment, but the RMS relapsed and the child developed multiple refractory metastatic foci and succumbed to his disease. CONCLUSIONS: Non-ocular SPTs like sarcomas are usually known to manifest in heritable rb survivors with a lag of two to three decades (earlier if exposure to radiation is present) from the presentation of the rb. However, in our case, this seemed to be reversed with the RMS being manifest at an unusual early age and the rb being diagnosed at a later point in time.


Assuntos
Segunda Neoplasia Primária , Neoplasias da Retina , Retinoblastoma , Rabdomiossarcoma , Criança , Humanos , Mutação , Segunda Neoplasia Primária/diagnóstico , Segunda Neoplasia Primária/genética , Neoplasias da Retina/diagnóstico , Neoplasias da Retina/genética , Neoplasias da Retina/patologia , Retinoblastoma/diagnóstico , Retinoblastoma/genética , Retinoblastoma/patologia , Rabdomiossarcoma/diagnóstico , Rabdomiossarcoma/genética , Gêmeos Monozigóticos
17.
Ophthalmic Res ; 67(1): 172-182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38160664

RESUMO

INTRODUCTION: Mutational screening of inherited retinal disorders is prerequisite for gene targeted therapy. Our aim was to report and analyze the proportions of mutations in inherited retinal disease (IRD)-causing genes from a single center in Switzerland in order to describe the distribution of IRDs in Western Switzerland. METHODS: We conducted a retrospective study of patient records. Criteria for inclusion were residence in Western Switzerland for patients and relatives presenting a clinical diagnosis of IRDs and an established molecular diagnosis managed by the genetics service of the Jules-Gonin Eye Hospital (JGEH) of Lausanne between January 2002 and December 2022. We initially investigated the IRD phenotypes in all patients (full cohort) with a clinical diagnosis, then calculated the distribution of IRD gene mutations in the entire cohort (genetically determined cohort). We analyzed a sub-group that comprised pediatric patients (≤18 years of age). In addition, we calculated the distribution of gene mutations within the most represented IRDs. Comprehensive gene screening was performed using a combined approach of different generation of DNA microarray analysis, direct sequencing, and Sanger sequencing. RESULTS: The full cohort comprised 899 individuals from 690 families with a clinical diagnosis of IRDs. We identified 400 individuals from 285 families with an elucidated molecular diagnosis (variants in 84 genes) in the genetically determined cohort. The pediatric cohort included 89 individuals from 65 families with an elucidated molecular diagnosis. The molecular diagnosis rate for the genetically determined cohort was 58.2% (family ratio) and the 5 most frequently implicated genes per family were ABCA4 (11.6%), USH2A (7.4%), EYS (6.7%), PRPH2 (6.3%), and BEST1 (4.6%). The pediatric cohort had a family molecular diagnosis rate of 64.4% and the 5 most common mutated genes per family were RS1 (9.2%), ABCA4 (7.7%), CNGB3 (7.7%), CACNA1F (6.2%), CEP290 (4.6%). CONCLUSIONS: This study describes the genetic mutation landscape of IRDs in Western Switzerland in order to quantify their disease burden and contribute to a better orientation of the development of future gene targeted therapies.


Assuntos
Proteínas do Olho , Mutação , Retinose Pigmentar , Humanos , Estudos Retrospectivos , Masculino , Feminino , Suíça/epidemiologia , Retinose Pigmentar/genética , Retinose Pigmentar/diagnóstico , Criança , Adulto , Adolescente , Análise Mutacional de DNA , Pessoa de Meia-Idade , Proteínas do Olho/genética , Pré-Escolar , Linhagem , Adulto Jovem , Idoso , Fenótipo , Testes Genéticos/métodos , Lactente
18.
Ecotoxicol Environ Saf ; 278: 116390, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38705037

RESUMO

Microplastics (MPs) and benzo[a]pyrene (B[a]P) are prevalent environmental pollutants. Numerous studies have extensively reported their individual adverse effects on organisms. However, the combined effects and mechanisms of exposure in mammals remain unknown. Thus, this study aims to investigate the potential effects of oral administration of 0.5µm polystyrene (PS) MPs (1 mg/mL or 5 mg/mL), B[a]P (1 mg/mL or 5 mg/mL) and combined (1 mg/mL or 5 mg/mL) on 64 male SD rats by gavage method over 6-weeks. The results demonstrate that the liver histopathological examination showed that the liver lobules in the combined (5 mg/kg) group had blurred and loose boundaries, liver cord morphological disorders, and significant steatosis. The levels of AST, ALT, TC, and TG in the combined dose groups were significantly higher than those in the other groups, the combined (5 mg/kg) group had the lowest levels of antioxidant enzymes and the highest levels of oxidants. The expression of Nrf2 was lowest and the expression of P38, NF-κB, and TNF-α was highest in the combined (5 mg/kg) group. In conclusion, these findings indicate that the combination of PSMPs and B[a]P can cause the highest levels of oxidative stress and elicit markedly enhanced toxic effects, which cause severe liver damage.


Assuntos
Benzo(a)pireno , Fígado , Microplásticos , Estresse Oxidativo , Poliestirenos , Ratos Sprague-Dawley , Animais , Estresse Oxidativo/efeitos dos fármacos , Benzo(a)pireno/toxicidade , Microplásticos/toxicidade , Masculino , Poliestirenos/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Ratos , Poluentes Ambientais/toxicidade , Antioxidantes/metabolismo , NF-kappa B/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo
19.
Health Res Policy Syst ; 22(1): 112, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160603

RESUMO

BACKGROUND: Multi-drug-resistant tuberculosis (MDR-TB) infections are a public health concern. Since 2017, the Ministry of Health (MoH) in Zambia, in collaboration with its partners, has been implementing decentralised MDR-TB services to address the limited community access to treatment. This study sought to explore the role of collaboration in the implementation of decentralised multi drug-resistant tuberculosis services in Zambia. METHODS: A qualitative case study design was conducted in selected provinces in Zambia using in-depth and key informant interviews as data collection methods. We conducted a total of 112 interviews involving 18 healthcare workers, 17 community health workers, 32 patients and 21 caregivers in healthcare facilities located in 10 selected districts. Additionally, 24 key informant interviews were conducted with healthcare workers managers at facility, district, provincial, and national-levels. Thematic analysis was employed guided by the Integrative Framework for Collaborative Governance. FINDINGS: The principled engagement was shaped by the global health agenda/summit meeting influence on the decentralisation of TB, engagement of stakeholders to initiate decentralisation, a supportive policy environment for the decentralisation process and guidelines and quarterly clinical expert committee meetings. The factors that influenced the shared motivation for the introduction of MDR-TB decentralisation included actors having a common understanding, limited access to health facilities and emergency transport services, a shared understanding of challenges in providing optimal patient monitoring and review and their appreciation of the value of evidence-based decision-making in the implementation of MDR- TB decentralisation. The capacity for joint action strategies included MoH initiating strategic partnerships in enhancing MDR-TB decentralisation, the role of leadership in organising training of healthcare workers and of multidisciplinary teams, inadequate coordination, supervision and monitoring of laboratory services and joint action in health infrastructural rehabilitation. CONCLUSIONS: Principled engagement facilitated the involvement of various stakeholders, the dissemination of relevant policies and guidelines and regular quarterly meetings of clinical expert committees to ensure ongoing support and guidance. A shared motivation among actors was underpinned by a common understanding of the barriers faced while implementing decentralisation efforts. The capacity for joint action was demonstrated through several key strategies, however, challenges such as inadequate coordination, supervision and monitoring of laboratory services, as well as the need for collaborative efforts in health infrastructural rehabilitation were observed. Overall, collaboration has facilitated the creation of a more responsive and comprehensive TB care system, addressing the critical needs of patients and improving health outcomes.


Assuntos
Pessoal de Saúde , Política de Saúde , Pesquisa Qualitativa , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Zâmbia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Política , Participação dos Interessados , Acessibilidade aos Serviços de Saúde/organização & administração , Atenção à Saúde/organização & administração , Comportamento Cooperativo , Agentes Comunitários de Saúde/organização & administração , Feminino , Masculino
20.
Cancer Sci ; 114(9): 3728-3739, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37340597

RESUMO

Retinoblastoma is the most common pediatric eye cancer. It is currently treated with a limited number of drugs, adapted from other pediatric cancer treatments. Drug toxicity and relapse of the disease warrant new therapeutic strategies for these young patients. In this study, we developed a robust tumoroid-based platform to test chemotherapeutic agents in combination with focal therapy (thermotherapy) - a treatment option widely used in clinical practice - in accordance with clinically relevant trial protocols. The model consists of matrix-embedded tumoroids that retain retinoblastoma features and respond to repeated chemotherapeutic drug exposure similarly to advanced clinical cases. Moreover, the screening platform includes a diode laser (810 nm, 0.3 W) to selectively heat the tumoroids, combined with an on-line system to monitor the intratumoral and surrounding temperatures. This allows the reproduction of the clinical settings of thermotherapy and combined chemothermotherapy treatments. When testing the two main drugs currently used in clinics to treat retinoblastoma in our model, we observed results similar to those clinically obtained, validating the utility of the model. This screening platform is the first system to accurately reproduce clinically relevant treatment methods and should lead to the identification of more efficient drugs to treat retinoblastoma.


Assuntos
Neoplasias da Retina , Retinoblastoma , Criança , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias da Retina/tratamento farmacológico , Retinoblastoma/tratamento farmacológico
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