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1.
Cell ; 167(7): 1674-1676, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27984717

RESUMO

Using induced pluripotent stem cells, Ang et al. elucidate how a mutation in the transcription factor GATA4 causes congenital heart disease. They find that, although the recruitment of GATA4 to cardiac super-enhancers is retained, it no longer functions in partnership with another key transcription factor, leading to misexpression of non-cardiomyocyte genes.


Assuntos
Fator de Transcrição GATA4/genética , Crise de Identidade , Coração , Humanos , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/genética
2.
Cell ; 157(3): 565-79, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24766806

RESUMO

The mammalian heart has a remarkable regenerative capacity for a short period of time after birth, after which the majority of cardiomyocytes permanently exit cell cycle. We sought to determine the primary postnatal event that results in cardiomyocyte cell-cycle arrest. We hypothesized that transition to the oxygen-rich postnatal environment is the upstream signal that results in cell-cycle arrest of cardiomyocytes. Here, we show that reactive oxygen species (ROS), oxidative DNA damage, and DNA damage response (DDR) markers significantly increase in the heart during the first postnatal week. Intriguingly, postnatal hypoxemia, ROS scavenging, or inhibition of DDR all prolong the postnatal proliferative window of cardiomyocytes, whereas hyperoxemia and ROS generators shorten it. These findings uncover a protective mechanism that mediates cardiomyocyte cell-cycle arrest in exchange for utilization of oxygen-dependent aerobic metabolism. Reduction of mitochondrial-dependent oxidative stress should be an important component of cardiomyocyte proliferation-based therapeutic approaches.


Assuntos
Pontos de Checagem do Ciclo Celular , Miócitos Cardíacos/citologia , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Sequestradores de Radicais Livres/farmacologia , Camundongos , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Peixe-Zebra
3.
Development ; 150(20)2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37883063

RESUMO

Metabolic switches are a crucial hallmark of cellular development and regeneration. In response to changes in their environment or physiological state, cells undergo coordinated metabolic switching that is necessary to execute biosynthetic demands of growth and repair. In this Review, we discuss how metabolic switches represent an evolutionarily conserved mechanism that orchestrates tissue development and regeneration, allowing cells to adapt rapidly to changing conditions during development and postnatally. We further explore the dynamic interplay between metabolism and how it is not only an output, but also a driver of cellular functions, such as cell proliferation and maturation. Finally, we underscore the epigenetic and cellular mechanisms by which metabolic switches mediate biosynthetic needs during development and regeneration, and how understanding these mechanisms is important for advancing our knowledge of tissue development and devising new strategies to promote tissue regeneration.


Assuntos
Diferenciação Celular , Proliferação de Células
4.
Circulation ; 149(23): 1833-1851, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38586957

RESUMO

BACKGROUND: Adult mammalian cardiomyocytes have limited proliferative capacity, but in specifically induced contexts they traverse through cell-cycle reentry, offering the potential for heart regeneration. Endogenous cardiomyocyte proliferation is preceded by cardiomyocyte dedifferentiation (CMDD), wherein adult cardiomyocytes revert to a less matured state that is distinct from the classical myocardial fetal stress gene response associated with heart failure. However, very little is known about CMDD as a defined cardiomyocyte cell state in transition. METHODS: Here, we leveraged 2 models of in vitro cultured adult mouse cardiomyocytes and in vivo adeno-associated virus serotype 9 cardiomyocyte-targeted delivery of reprogramming factors (Oct4, Sox2, Klf4, and Myc) in adult mice to study CMDD. We profiled their transcriptomes using RNA sequencing, in combination with multiple published data sets, with the aim of identifying a common denominator for tracking CMDD. RESULTS: RNA sequencing and integrated analysis identified Asparagine Synthetase (Asns) as a unique molecular marker gene well correlated with CMDD, required for increased asparagine and also for distinct fluxes in other amino acids. Although Asns overexpression in Oct4, Sox2, Klf4, and Myc cardiomyocytes augmented hallmarks of CMDD, Asns deficiency led to defective regeneration in the neonatal mouse myocardial infarction model, increased cell death of cultured adult cardiomyocytes, and reduced cell cycle in Oct4, Sox2, Klf4, and Myc cardiomyocytes, at least in part through disrupting the mammalian target of rapamycin complex 1 pathway. CONCLUSIONS: We discovered a novel gene Asns as both a molecular marker and an essential mediator, marking a distinct threshold that appears in common for at least 4 models of CMDD, and revealing an Asns/mammalian target of rapamycin complex 1 axis dependency for dedifferentiating cardiomyocytes. Further study will be needed to extrapolate and assess its relevance to other cell state transitions as well as in heart regeneration.


Assuntos
Aspartato-Amônia Ligase , Desdiferenciação Celular , Fator 4 Semelhante a Kruppel , Miócitos Cardíacos , Animais , Camundongos , Aspartato-Amônia Ligase/genética , Aspartato-Amônia Ligase/metabolismo , Células Cultivadas , Miócitos Cardíacos/metabolismo , Carbono-Nitrogênio Ligases com Glutamina como Doadora de N-Amida/genética , Carbono-Nitrogênio Ligases com Glutamina como Doadora de N-Amida/metabolismo
5.
J Mol Cell Cardiol ; 187: 15-25, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38141532

RESUMO

The metabolic switch from glycolysis to fatty acid oxidation in postnatal cardiomyocytes contributes to the loss of the cardiac regenerative potential of the mammalian heart. However, the mechanisms that regulate this metabolic switch remain unclear. The protein kinase complex mechanistic target of rapamycin complex 1 (mTORC1) is a central signaling hub that regulates cellular metabolism and protein synthesis, yet its role during mammalian heart regeneration and postnatal metabolic maturation is undefined. Here, we use immunoblotting, rapamycin treatment, myocardial infarction, and global proteomics to define the role of mTORC1 in postnatal heart development and regeneration. Our results demonstrate that the activity of mTORC1 is dynamically regulated between the regenerating and the non-regenerating hearts. Acute inhibition of mTORC1 by rapamycin or everolimus reduces cardiomyocyte proliferation and inhibits neonatal heart regeneration following injury. Our quantitative proteomic analysis demonstrates that transient inhibition of mTORC1 during neonatal heart injury did not reduce protein synthesis, but rather shifts the cardiac proteome of the neonatal injured heart from glycolysis towards fatty acid oxidation. This indicates that mTORC1 inhibition following injury accelerates the postnatal metabolic switch, which promotes metabolic maturation and impedes cardiomyocyte proliferation and heart regeneration. Taken together, our results define an important role for mTORC1 in regulating postnatal cardiac metabolism and may represent a novel target to modulate cardiac metabolism and promote heart regeneration.


Assuntos
Miócitos Cardíacos , Proteômica , Animais , Miócitos Cardíacos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Animais Recém-Nascidos , Coração/fisiologia , Sirolimo , Ácidos Graxos/metabolismo , Proliferação de Células , Mamíferos/metabolismo
6.
Prostate ; 84(3): 237-244, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37899635

RESUMO

BACKGROUND: Prostate cancer (PCa) parenchymal brain metastases are uncommon and troubling observations in the course of the disease. Our study aims to evaluate the prevalence of brain metastases among PCa patients while reporting various therapeutic modalities, clinical features, and oncological outcomes. METHODS: We retrospectively identified 34 patients with parenchymal brain metastasis out of 4575 patients using a prospectively maintained database that contains clinicopathologic characteristics of PCa patients between January 2012 and December 2021. Based on the three treatment modalities used, the patients were divided into three groups: stereotactic radiosurgery (SRS), whole brain radiotherapy (WBRT), and systemic therapy alone. The Kaplan-Meier curve was used to calculate overall survival [OS] probability and the Cox proportional hazards regression model was used to compare between groups. RESULTS: At the time of brain metastasis diagnosis, the median age was 66 years, the median (interquartile range [IQR]) prostate-specific antigen (PSA) was 2.2 (0.1-26.6) ng/ml and the median (IQR) months from initial PCa diagnosis to brain metastasis development was 70.8 (27.6-100.9). The median (IQR) primary Gleason score was 8 (7-9) and over a median (IQR) follow-up time of 2.2 (1.2-16.5) months, 76.5% (n = 26) of the patients died. Thirteen (38.2%) patients had solitary lesion, whereas 21 (61.8%) had ≥2 lesions. The lesions were supratentorial in 19 (55.9%) patients, infratentorial in six (17.6%), and both sides in nine (26.5%). Among all 34 patients, 10 (29.4%) were treated with SRS, seven (20.6%) with WBRT, and 17 (50%) with systemic therapy alone. OS varied greatly between the three treatment modalities (log-rank test, p = 0.049). Those who were treated with SRS and WBRT had better OS compared with patients who were treated with systemic therapy alone (hazard ratio: 0.37, 95% confidence interval: 0.16-0.86, p = 0.022). CONCLUSIONS: In our single-institutional study, we confirmed that PCa brain metastasis is associated with poor survival outcomes and more advanced metastatic disease. Furthermore, we found that SRS and WBRT for brain metastasis in patients with recurrent PCa appear to be associated with improved OS as compared with systemic therapy alone and are likely secondary to selection bias.


Assuntos
Neoplasias Encefálicas , Neoplasias da Próstata , Radiocirurgia , Masculino , Humanos , Lactente , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/secundário , Neoplasias da Próstata/cirurgia
7.
Neurocase ; 30(2): 77-82, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38795053

RESUMO

L-2-hydroxyglutaric aciduria (L-2-HGA) is a rare autosomal recessive disease characterized by elevated levels of hydroxyglutaric acid in the body fluids and brain with abnormal white matter. We present two siblings with psychomotor retardation and quadriparesis. Their brain imaging showed diffuse bilateral symmetrical involvement of the cerebral cortex, white matter, basal ganglia and cerebellum. The whole exome sequence studies revealed a homozygous likely pathogenic variant on chromosome 14q22.1 (NM_024884.2: c.178G > A; pGly60Arg) in the gene encoding for L-2-hydroxyglutarate dehydrogenase (L2HGDH) (OMIM #236792). Therefore, using the L2HGDH gene study is beneficial for L2HGA diagnosis.


Assuntos
Oxirredutases do Álcool , Irmãos , Criança , Humanos , Oxirredutases do Álcool/genética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/diagnóstico por imagem , Encefalopatias Metabólicas/diagnóstico , Encefalopatias Metabólicas Congênitas/genética , Encefalopatias Metabólicas Congênitas/diagnóstico , Encefalopatias Metabólicas Congênitas/diagnóstico por imagem , Egito , Imageamento por Ressonância Magnética
8.
Artigo em Inglês | MEDLINE | ID: mdl-39113229

RESUMO

A new and innovative rolled graphene oxide (roll-GO)/poly-m-methylaniline (PmMA) core-shell nanocomposite has been successfully synthesized using an in situ polymerization technique. This eco-friendly and cost-effective material shows great promise due to its antimicrobial properties. The characterization of the nanocomposite involved X-ray diffraction and Fourier transform infrared spectroscopy to analyze its structure and functional groups, whereas scanning electron microscopy and transmission electron microscopy (TEM) were utilized to examine its morphology. TEM analysis revealed the formation of roll-GO, forming multi-walled tubes with inner and outer diameters of 50 and 70 nm, respectively. Optical analysis demonstrated an enhanced bandgap in the nanocomposite, with bandgap values of 2.38 eV for PmMA, 2.67 eV for roll-GO, and 1.65 eV for roll-GO/PmMA. The antibacterial efficacy of the nanocomposite was tested against Gram-positive bacteria, including Bacillus subtilis and Staphylococcus aureus, as well as Gram-negative bacteria such as Escherichia coli and Salmonella sp. The well diffusion method was used to determine the inhibition zones, revealing that the nanocomposite demonstrated broad-spectrum antibacterial activity against all the pathogens tested. The largest inhibition zones were observed for B. subtilis, followed by S. aureus, E. coli, and Salmonella sp. Notably, the inhibition zones increased when the samples were exposed to light compared to dark conditions, with increases of 33 and 18 mm noted for B. subtilis. This enhanced activity under light exposure is attributed to the photocatalytic properties of the nanocomposite. The antibacterial mechanism is based on both adsorption and degradation processes. Moreover, antibacterial activity was found to increase with increasing concentrations of nanoparticles, ranging from 100 to 500 ppm. This suggests that the nanocomposite has potential as an alternative to antibiotics, especially considering the growing issue of bacterial resistance. The promising results obtained from the inhibition zones make these nanocomposites suitable for various applications. Currently, the research team is working on the development of a prototype utilizing these antimicrobial particles within commercial bottles for sterilization purposes in factories and companies.

9.
Food Microbiol ; 120: 104462, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431310

RESUMO

The antimicrobial effect of fresh garlic (20, 30, and 50 g/kg) and the equivalent concentrations of garlic oil (80, 120, and 200 mg/kg) was investigated in ground mutton during storage at 4 °C. By day 6 and thereafter, mutton meatballs treated with 50 g/kg of fresh garlic and 200 mg/kg garlic oil exhibited a significant decline in psychrotrophic and Pseudomonas counts in comparison with control. Fresh garlic added at a concentration of 50 g/kg exhibited the highest antimicrobial effect, followed by garlic oil at 200 mg/kg, fresh garlic at 30 g/kg, and garlic oil at 120 mg/kg. By the 15th day of storage, the fresh garlic added at concentrations of 50 and 30 g/kg and garlic oil added at concentrations of 120, and 200 mg/kg inactivated the populations of foodborne pathogens artificially inoculated into ground mutton and exhibited significant (P < 0.01) lower counts in Salmonella Typhimurium, Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus by more than 3 logs CFU/g, in comparison to control. Therefore, fresh garlic and garlic oil can be used as natural antimicrobial food additives to extend the shelf life and inactivate the populations of foodborne pathogens in meat products.


Assuntos
Compostos Alílicos , Alho , Listeria monocytogenes , Sulfetos , Microbiologia de Alimentos , Contagem de Colônia Microbiana , Salmonella typhimurium
10.
Sensors (Basel) ; 24(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-39000842

RESUMO

Ozone generation is a water disinfection method, superior to chlorine in terms of fewer byproducts and no residual taste. However, its high production cost limits its widespread adoption. This paper designs an ozone generation sinusoidal power supply for water treatment. Ozone generation requires a high-frequency and high-voltage power supply to produce ozone from oxygen molecules. The study evaluates two power supply topologies, one with a parallel LC filter and the other with an LCL filter, assessing their feasibility, effectiveness, and reliability. Theoretically, the LCL filter achieves higher gains than the parallel LC filter. The larger inductance in the parallel LC filter reduces gain, while the larger inductance in the LCL filter increases gain. Simulation and practical results validate these findings, achieving gains of 40 for the parallel LC filter and 150 for the LCL filter.

11.
BMC Nurs ; 23(1): 133, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378543

RESUMO

BACKGROUND: Climate change, a pervasive global phenomenon, exerts discernible impacts on the physical, social, and psychological dimensions of well-being. The apprehension surrounding this complex environmental issue has reached a critical juncture, with over 76,000 individuals across more than thirty nations expressing profound levels of concern, characterizing their anxiety as either "very" or "extremely" pronounced. This surge in awareness regarding the potential consequences of climate change has given rise to an emergent and escalating challenge known as climate anxiety. This distinctive form of anxiety manifests through profound feelings of fear, helplessness, and despair elicited by the impending repercussions of climate change. Notably, the intersection of climate anxiety with occupational domains, particularly within the context of Nursing University Colleagues, suggests a nuanced relationship with job engagement, wherein the psychological responses to climate change may influence professional commitment and involvement. AIM OF THE STUDY: To examine the correlation among Climate Anxiety, Environmental Attitude, and Job Engagement among Nursing University Colleagues comprising eight distinct nursing faculties. DESIGN: A multicenter descriptive, cross-sectional research design study followed. SUBJECT: Three hundred fifty-nine participants from the Centre, Delta, West, Suez Canal, and Upper regions of Egypt using a stratified random cluster sampling technique. MEASUREMENTS: Social and health related to climate data structured questionnaire, climate anxiety scale, environmental attitude inventory, and job engagement scale. RESULTS: The influence of demographics on climate anxiety, environmental attitude, and job involvement was not observed. Nevertheless, geographical variations emerged as a noteworthy factor. A statistically significant inverse correlation was identified between climate anxiety, job engagement dimensions, and the overall score of environmental attitudes. CONCLUSION: Climate anxiety was strongly associated with environmental attitudes and job engagement among nursing university colleagues. Higher climate anxiety is associated with a lower attitude towards the environment and decreased job engagement. Additionally, a higher attitude towards the environment is associated with decreased overall engagement in participants' jobs. IMPLICATIONS: The study's patterns make it clear how important it is to provide targeted psycho-educational interventions to help reduce climate anxiety among the group of nursing university colleagues. The imperative lies not only in alleviating the immediate psychological distress associated with heightened climate anxiety but also in fostering adaptive coping mechanisms. By doing so, these interventions serve as instrumental tools in nurturing resilience, thereby fortifying the mental well-being of nursing professionals amidst the evolving landscape of climate-related concerns.

12.
Worldviews Evid Based Nurs ; 21(2): 202-215, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38329153

RESUMO

BACKGROUND: Menopausal women often complain of a range of physical and psychological symptoms known as menopausal syndrome. These symptoms are associated with fluctuating hormone levels, sleep disturbances, and mood swings. AIM: This study aimed to examine the efficacy of a program-based cognitive behavioral group therapy (CBT) for insomnia and depression among women experiencing menopause. METHODS: A randomized controlled trial of 88 women experiencing menopause was conducted in Egypt from June to September 2022 in outpatient clinics at Mansoura University Hospitals in Egypt. Participants were randomly assigned to a control group (45 women) and an intervention group (43 women). The intervention group received 7 weeks of CBT sessions. Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), and Beck Depression Inventory 2nd Edition (BDI-II) were administered before and after the intervention. RESULTS: In the intervention group, there was a significant difference in scores of the subdomains of PSQI, including sleep efficiency, daytime dysfunction, subjective sleep quality, and sleep disturbance (t = 8.911, 11.77, 7.638, and 11.054, respectively), while no significant difference in domains of using sleep medication, sleep duration, and sleep latency. Significant improvements were observed between pre-and-post-intervention in the intervention group for the total scores of PSQI, ISI, and BDII-II (t = 12.711, 16.272, and 12.384, respectively), indicating a large effect size for the three studied variables (r = .81, .87, .8, respectively). LINKING EVIDENCE TO ACTION: This study demonstrated the efficacy of group CBT for lowering insomnia and depression in women experiencing menopause. Thus, results indicated the need of considering prompt and appropriate interventions such as CBT as a safe treatment option to prevent the aggravation of sleep and emotional problems for menopausal women. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05920460.


Assuntos
Terapia Cognitivo-Comportamental , Distúrbios do Início e da Manutenção do Sono , Humanos , Feminino , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/terapia , Depressão/complicações , Depressão/terapia , Sono , Menopausa , Terapia Cognitivo-Comportamental/métodos , Resultado do Tratamento
13.
Eur J Orthop Surg Traumatol ; 34(1): 389-395, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37540245

RESUMO

PURPOSE: Cerclage wiring is a well-known supplemental fixation technique that can be used in many types of fractures. With the tendency toward minimally invasive approaches in the management of periprosthetic total knee arthroplasty (TKA) fractures, and with absence of a dedicated study that reports the results of cerclage wiring in TKA fractures in particular, the aim of this retrospective study is to report the outcomes of supplementary cerclage wiring using simple Luque wires in fractures of distal femur associated with TKA. METHOD: Eighteen cases, with a mean age of 77.2 years had complete follow-up data and had their radiographs and clinical data assessed for this study. Patients received cerclage wiring along with plates, retrograde nailing or around cracked femoral shaft overlying revision TKA femoral stem during the surgical management of periprosthetic TKA distal femur fractures. RESULTS: Fracture healing with adequate callus formation occurred in all 18 cases at a mean of 11.4 weeks postoperatively. None of the cases had any vascular injury, and after a mean clinical follow-up of 51 weeks, none of the cases had nonunion or hardware complications. One case had postoperative periprosthetic infection that developed 8 months after full fracture healing and had a two-stage revision using revision stemmed TKA and protective cerclage wiring with successful eradication of infection. CONCLUSION: Supplementary cerclage wiring in distal femur TKA fractures can aid in enhanced bone healing with minimal complications, provided that adequate reduction and rigid fixation were achieved. This study reflects the level of evidence IV.


Assuntos
Artroplastia do Joelho , Fraturas do Fêmur , Fraturas Periprotéticas , Humanos , Idoso , Estudos Retrospectivos , Artroplastia do Joelho/efeitos adversos , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Placas Ósseas/efeitos adversos , Resultado do Tratamento
14.
J Mol Cell Cardiol ; 176: 33-40, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36657638

RESUMO

The neonatal swine heart possesses an endogenous ability to regenerate injured myocardium through the proliferation of pre-existing cardiomyocyte (CM) populations. However, this regenerative capacity is lost shortly after birth. Normal postnatal developmental processes and the regenerative capacity of mammalian hearts are tightly linked, but not much is known about how the swine cardiac proteome changes throughout postnatal development. Herein, we integrated robust and quantitative targeted "top-down" and global "bottom-up" proteomic workflows to comprehensively define the dynamic landscape of the swine cardiac proteome throughout postnatal maturation. Using targeted top-down proteomics, we were able to identify significant alterations in sarcomere composition, providing new insight into the proteoform landscape of sarcomeres that can disassemble, a process necessary for productive CM proliferation. Furthermore, we quantified global changes in protein abundance using bottom-up proteomics, identified over 700 differentially expressed proteins throughout postnatal development, and mapped these proteins to changes in developmental and metabolic processes. We envision these results will help guide future investigations to comprehensively understand endogenous cardiac regeneration toward the development of novel therapeutic strategies for heart failure.


Assuntos
Proteoma , Sarcômeros , Animais , Suínos , Sarcômeros/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Coração , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Mamíferos/metabolismo
15.
Semin Cell Dev Biol ; 118: 136-143, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33931308

RESUMO

The heart undergoes profound morphological and functional changes as it continues to mature postnatally. However, this phase of cardiac development remains understudied. More recently, cardiac maturation research has attracted a lot of interest due to the need for more mature stem cell-derived cardiomyocytes for disease modeling, drug screening and heart regeneration. Additionally, neonatal heart injury models have been utilized to study heart regeneration, and factors regulating postnatal heart development have been associated with adult cardiac disease. Critical components of cardiac maturation are systemic and local biochemical cues. Specifically, cardiac innervation and the concentration of various metabolic hormones appear to increase perinatally and they have striking effects on cardiomyocytes. Here, we first report some of the key parameters of mature cardiomyocytes and then discuss the specific effects of neurons and hormonal cues on cardiomyocyte maturation. We focus primarily on the structural, electrophysiologic, metabolic, hypertrophic and hyperplastic effects of each factor. This review highlights the significance of underappreciated regulators of cardiac maturation and underscores the need for further research in this exciting field.


Assuntos
Hormônios/metabolismo , Miócitos Cardíacos/fisiologia , Neurônios/metabolismo , Humanos
16.
Clin Infect Dis ; 76(3): e308-e318, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35675306

RESUMO

BACKGROUND: The Middle East respiratory syndrome coronavirus (MERS-CoV) is a highly pathogenic zoonotic betacoronavirus and a global public health concern. Better undersetting of the immune responses to MERS-CoV is needed to characterize the correlates of protection and durability of the immunity and to aid in developing preventative and therapeutic interventions. Although MERS-CoV-specific circulating antibodies could persist for several years post-recovery, their waning raises concerns about their durability and role in protection. Nonetheless, memory B and T cells could provide long-lasting protective immunity despite the serum antibodies levels. METHODS: Serological and flow cytometric analysis of MERS-CoV-specific immune responses were performed on samples collected from a cohort of recovered individuals who required intensive care unit (ICU) admission as well as hospital or home isolation several years after infection to characterize the longevity and quality of humoral and cellular immune responses. RESULTS: Our data showed that MERS-CoV infection could elicit robust long-lasting virus-specific binding and neutralizing antibodies as well as T- and B-cell responses up to 6.9 years postinfection regardless of disease severity or need for ICU admission. Apart from the persistent high antibody titers, this response was characterized by B-cell subsets with antibody-independent functions as demonstrated by their ability to produce tumor necrosis factor α (TNF-α), interleukin (IL)-6, and interferon γ (IFN-γ) cytokines in response to antigen stimulation. Furthermore, virus-specific activation of memory CD8+ and CD4+ T cell subsets from MERS-recovered patients resulted in secretion of high levels of TNF-α, IL-17, and IFN-γ. CONCLUSIONS: MERS-CoV infection could elicit robust long-lasting virus-specific humoral and cellular responses.


Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Infecções por Coronavirus/prevenção & controle , Imunidade Celular , Interferon gama , Fator de Necrose Tumoral alfa , Linfócitos T/imunologia , Linfócitos B/imunologia
17.
Oncologist ; 28(4): 297-308, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36745503

RESUMO

Renal cell carcinoma (RCC) is among the top 10 most common cancers in both men and women with an estimated 75 000 cases each year in the US. Over the last decade, the therapeutic landscape for patients with metastatic RCC has significantly evolved, with immunotherapy emerging as the new front-line therapy. Despite significant improvement in toxicity profile and survival outcomes, key concerns such as patient selection, treatment sequencing, and intrinsic and acquired resistance remain unresolved. Emerging options such as antibody-based therapeutics (eg, anti-CD70, anti-CA9, and anti-ENPP3) are being explored in clinical trials for patients with cancer resistant or refractory to current immunotherapies. Despite positive results for hematological cancers, breast cancer, and more recently bladder cancer, most antibody-based therapies failed to improve the outcomes in patients with advanced RCC. This underscores the need to understand the underlying causes of failed responses to this treatment class, which will ultimately support the rational design of more effective and tolerable treatments. In this review, we summarize the evolving landscape of RCC therapeutics and describe recent clinical trials with emerging antibody-based therapeutics. We also describe the challenges that need to be overcome for the successful creation of therapeutic antibodies for treating RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Masculino , Humanos , Feminino , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Imunoterapia/métodos , Anticorpos
18.
BMC Microbiol ; 23(1): 269, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752474

RESUMO

BACKGROUND: Toxigenic fungi (Aspergillus and Fusarium) and their metabolites represent the major cause of corn and corn-based products contamination and consequently lead to severe economic and health issues. AIM: Our current study aimed to investigate the efficacy of using L. macroides Bac6 as a biological control agent against the toxigenic fungi; A. flavus f10 and F. proliferatum f30 and their mycotoxins. RESULTS: The results illustrated that A. flavus f10 produced the aflatoxins AFB1 and AFG2 with concentrations of 21.239 and 13.593 ppb, respectively. While F. proliferatum f30 produced fumonisin B1 (9600 ppb). Furthermore, L. macroides showed a high potential for inhibition of toxigenic fungal growth using a dual culture method. F. proliferatum f30 and A. flavus f10 were found to be inhibited by a percentage of 80 and 62.5%, respectively. The results were confirmed using the scanning electron microscope. The antagonistic bacteria, L. macroides, showed chitinase productivity and activity of 26.45 U/L and 0.12 U/mL/min, respectively, which illustrates its potential application as a biocontrol agent. The GC-MS analysis revealed an abundance of Pyrrolo[1,2-a] pyrazine-1,4-dione, Hexahydro in the bacterial supernatant that exhibited antifungal characteristics. L. macroides had a significant reduction of AFB1 and AFG2 produced by A. flavus f10, recording 99.25% and 99% inhibition, respectively. It also showed strong inhibition of fumonisin B1 (90% inhibition) produced by F. proliferatum f30. CONCLUSION: Thus, the current study is a prospective study evaluating for the first time the potential impact of L. macroides Bac6 against the toxigenic fungi and their toxins.


Assuntos
Fusarium , Micotoxinas , Micotoxinas/farmacologia , Aspergillus flavus , Antifúngicos/farmacologia , Estudos Prospectivos
19.
Opt Express ; 31(9): 14278-14285, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157295

RESUMO

The unidirectional flow of electrons that takes place in a conventional electronic diode has been a cornerstone in the development of the field of electronics. Achieving an equivalent one-way flow for light has been a long-standing problem. While a number of concepts have been suggested recently, attaining a unidirectional flow of light in a two-port system (e.g., a waveguiding configuration) is still challenging. Here, we present what we believe to be a novel approach for breaking reciprocity and achieving one-way flow of light. Taking a nanoplasmonic waveguide as an example, we show that a combination of time-dependent interband optical transitions, when in systems exhibiting a backward wave flow, can yield light transmission strictly in one direction. In our configuration, the energy flow is unidirectional: light is fully reflected in one direction of propagation, and is unperturbed in the other. The concept can find use in a range of applications including communications, smart windows, thermal radiation management, and solar energy harvesting.

20.
Virol J ; 20(1): 241, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875904

RESUMO

BACKGROUND: Coronavirus disease 19 (COVID-19) is the disease caused by SARS-CoV-2, a highly infectious member of the coronavirus family, which emerged in December 2019 in "Wuhan, China". It induces respiratory illness ranging from mild symptoms to severe disease. It was declared a "pandemic" by the World Health Organization (WHO) in March 2020. Since then, a vast number of clinical and experimental studies have been conducted to identify effective approaches for its prevention and treatment. MAIN BODY: The pathophysiology of COVID-19 represents an unprecedented challenge; it triggers a strong immune response, which may be exacerbated by "a cytokine storm syndrome". It also induces thrombogenesis and may trigger multi-organ injury. Therefore, different drug classes have been proposed for its treatment and prevention, such as antivirals, anti-SARS-CoV-2 antibody agents (monoclonal antibodies, convalescent plasma, and immunoglobulins), anti-inflammatory drugs, immunomodulators, and anticoagulant drugs. To the best of our knowledge, this review is the first to present, discuss, and summarize the current knowledge about the different drug classes used for the treatment of COVID-19, with special emphasis on their targets, mechanisms of action, and important adverse effects and drug interactions. Additionally, we spotlight the latest "October 2023" important guidelines (NIH, IDSA, and NICE) and FDA approval or authorization regarding the use of these agents in the management of COVID-19. CONCLUSION: Despite the wide array of therapeutic strategies introduced for the treatment of COVID-19, one of the most prominent therapeutic challenges is SARS-CoV-2 mutations and emerging new variants and subvariants. Currently, the anti-COVID-19 drug pipeline is continuously affording novel treatments to face this growing challenge.


Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/uso terapêutico , Antivirais/farmacologia , SARS-CoV-2 , Anticorpos Antivirais , Anticorpos Monoclonais
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