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1.
Meat Sci ; 183: 108646, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34392092

RESUMO

The objective of this study was to investigate if ultrasonication of bovine longissimus thoracis et lumborum (LTL) steaks increases calpain-1 and caspase-3 activities, and if so, to explore the underlying mechanisms that trigger their activation. Post-rigor bovine LTL steaks were subjected to ultrasonication at 40 kHz and 12 W/cm2 for 40 min and subsequently aged for 14 d at 4 °C. Ultrasonication improved beef tenderness (P < 0.05) without negatively impacting pH, color, or cook loss (P > 0.05). Improved tenderness in the ultrasonicated steaks was associated with greater degradation of titin, desmin, troponin-T, and calpastatin and increased calpain-1 autolysis and caspase-3 activity (P < 0.05). In addition, ultrasonicated steaks had greater levels of cytosolic calcium and reactive oxygen species and lower mitochondrial oxygen consumption rate (P < 0.05). These data indicate that improved beef tenderness following ultrasonication is, in part, a function of increased calpain-1 and caspase-3 activities, potentially by elevating cytosolic calcium and inducing mitochondrial dysfunction, respectively.


Assuntos
Calpaína/metabolismo , Caspase 3/metabolismo , Carne Vermelha/análise , Ondas Ultrassônicas , Animais , Cálcio/metabolismo , Bovinos , Masculino , Mitocôndrias/efeitos da radiação , Resistência ao Cisalhamento
2.
J Sci Food Agric ; 102(1): 299-311, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34091912

RESUMO

BACKGROUND: Stevia rebaudiana is a high value crop due to the strong commercial demand for its metabolites (steviol glycosides) but has limited geographical cultivation range. In non-native environments with different daylength and light quality, Stevia has low germination rates and early flowering resulting in lower biomass and poor yield of the desired metabolites. In this study, artificial lighting with light-emitting diodes (LEDs) was used to determine if different light quality within and outside of the photosynthetically active radiation (PAR) range can be used to improve germination rates and yields for production of steviol glycosides for the herbal supplement and food industry. RESULTS: Plants treated with red and blue light at an intensity of 130 µmol m-2  s-1 supplemented with 5% of UV-A light under a 16-h photoperiod produced the most desirable overall results with a high rate of germination, low percentage of early flowering, and high yields of dry leaf, stevioside and rebaudioside A, 175 days after planting. CONCLUSION: While red and blue light combinations are effective for plant growth, the use of supplemental non-PAR irradiation of UV-A wavelength significantly and desirably delayed flowering, enhanced germination, biomass, rebaudioside A and stevioside yields, while supplemental green light improved yield of biomass and rebaudioside A, but not stevioside. Overall, the combination of red, blue and UV-A light resulted in the best overall productivity for Stevia rebaudiana. © 2021 Society of Chemical Industry.


Assuntos
Flores/crescimento & desenvolvimento , Fotossíntese/efeitos da radiação , Sementes/efeitos da radiação , Stevia/crescimento & desenvolvimento , Biomassa , Diterpenos do Tipo Caurano/metabolismo , Flores/química , Flores/efeitos dos fármacos , Flores/metabolismo , Germinação , Glucosídeos/metabolismo , Luz , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Stevia/química , Stevia/metabolismo , Stevia/efeitos da radiação
3.
Folia Biol (Praha) ; 67(2): 62-69, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34624938

RESUMO

Hypoxia leads to post-treatment metastasis and recurrences of cancer via the epithelial-mesenchymal transition (EMT). Radiotherapy itself may also contribute to the acquisition of EMT phenotypes. Despite extensive studies on the EMT driven by either hypoxia or radiation stimuli, the molecular mechanisms characterizing these EMT events remain unclear. Thus, we aimed to evaluate the differences in the molecular pathways between hypoxia-induced EMT (Hypo-EMT) and radiation-induced EMT (R-EMT). Further, we investigated the therapeutic effects of HIF-1α inhibitor (LW6) on Hypo-EMT and R-EMT cells. A549 cells, lung adenocarcinoma cell line, acquired enhanced wound-healing activity under both hypoxia and irradiation. Localization of E-cadherin was altered from the cell membrane to the cytoplasm in both hypoxia and irradiated conditions. Of note, the expression levels of vimentin, one of the major EMT markers, was enhanced in irradiated cells, while it decreased under hypoxia condition. Importantly, LW6 significantly blocked EMT-related malignant phenotypes in both Hypo-EMT cells and R-EMT cells with concomitant re-location of E-cadherin onto the cell membrane. Moreover, LW6 deflected stress responsive signalling, JNK, activated sustainably under hypoxic condition, and the blockage of JNK impaired EMT phenotypes. Together, this work demonstrated the molecular events underlying Hypo-EMT and R-EMT, and highlighted HIF-1α as a therapeutic target not only in Hypo- EMT, but also in R-EMT.


Assuntos
Hipóxia Celular , Transição Epitelial-Mesenquimal , Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Pulmonares , Células A549 , Antígenos CD , Caderinas , Transição Epitelial-Mesenquimal/efeitos da radiação , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia
4.
Nat Commun ; 12(1): 5735, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593790

RESUMO

Control over the stereochemistry of excited-state photoreactions remains a significant challenge in organic synthesis. Recently, it has become recognized that the photophysical properties of simple organic substrates can be altered upon coordination to Lewis acid catalysts, and that these changes can be exploited in the design of highly enantioselective catalytic photoreactions. Chromophore activation strategies, wherein simple organic substrates are activated towards photoexcitation upon binding to a Lewis acid catalyst, rank among the most successful asymmetric photoreactions. Herein, we show that chiral Brønsted acids can also catalyze asymmetric excited-state photoreactions by chromophore activation. This principle is demonstrated in the context of a highly enantio- and diastereoselective [2+2] photocycloaddition catalyzed by a chiral phosphoramide organocatalyst. Notably, the cyclobutane products arising from this method feature a trans-cis stereochemistry that is complementary to other enantioselective catalytic [2+2] photocycloadditions reported to date.


Assuntos
Reação de Cicloadição/métodos , Luz , Catálise/efeitos da radiação , Estrutura Molecular , Estereoisomerismo
5.
Sci Rep ; 11(1): 19470, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593848

RESUMO

The germicidal potential of specific wavelengths within the electromagnetic spectrum is an area of growing interest. While ultra-violet (UV) based technologies have shown satisfactory virucidal potential, the photo-toxicity in humans coupled with UV associated polymer degradation limit their use in occupied spaces. Alternatively, longer wavelengths with less irradiation energy such as visible light (405 nm) have largely been explored in the context of bactericidal and fungicidal applications. Such studies indicated that 405 nm mediated inactivation is caused by the absorbance of porphyrins within the organism creating reactive oxygen species which result in free radical damage to its DNA and disruption of cellular functions. The virucidal potential of visible-light based technologies has been largely unexplored and speculated to be ineffective given the lack of porphyrins in viruses. The current study demonstrated increased susceptibility of lipid-enveloped respiratory pathogens of importance such as SARS-CoV-2 (causative agent of COVID-19) and influenza A virus to 405 nm, visible light in the absence of exogenous photosensitizers thereby indicating a potential alternative porphyrin-independent mechanism of visible light mediated viral inactivation. These results were obtained using less than expected irradiance levels which are considered safe for humans and commercially achievable. Our results support further exploration of the use of visible light technology for the application of continuous decontamination in occupied areas within hospitals and/or infectious disease laboratories, specifically for the inactivation of respiratory pathogens such as SARS-CoV-2 and Influenza A.


Assuntos
Desinfecção/métodos , Vírus da Influenza A Subtipo H1N1/efeitos da radiação , SARS-CoV-2/efeitos da radiação , Desinfecção/instrumentação , Relação Dose-Resposta à Radiação , Vírus da Encefalomiocardite/efeitos da radiação , Luz , Fatores de Tempo , Inativação de Vírus/efeitos da radiação
6.
Gen Dent ; 69(6): 58-61, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34678745

RESUMO

This study aimed to assess the thermal effect of different light irradiation times on the setting time of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cements. This in vitro experimental study evaluated 40 hydraulic cement specimens, including 20 MTA and 20 CEM specimens, according to the manufacturers'instructions. For each cement, the specimens were divided into 3 test groups light cured with a halogen light-curing unit (n = 5 per group) and 1 control group (n = 5) that was not exposed to irradiation. The specimens in the MTA test groups were light cured for 20, 40, or 60 seconds, and the specimens in the CEM test groups were light cured for 60, 90, or 120 seconds. All test and control groups had 60 seconds of rest time. Setting of the cements was assessed at different timepoints using a Gillmore needle weighing 113.4 g with a 12.2-mm diameter according to ASTM C266-03 standards. The data were analyzed with the Fisher exact test and the Mann-Whitney U test (α = 0.05). The setting of MTA specimens after different curing times was significantly different (P < 0.05). The setting time of MTA control specimens was significantly longer than that of test specimens (P = 0.008). The setting of CEM specimens after different curing times was not significantly different (P > 0.05). However, the setting time for CEM control specimens was significantly longer than that for test specimens (P = 0.008). Light curing with a halogen light-curing unit can significantly decrease the setting time for MTA and CEM cements.


Assuntos
Compostos de Cálcio , Cimentos Dentários , Silicatos , Compostos de Alumínio , Cimentos Dentários/efeitos da radiação , Combinação de Medicamentos , Óxidos , Compostos de Fósforo
7.
Anticancer Res ; 41(10): 5001-5006, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34593448

RESUMO

BACKGROUND/AIM: To describe clinical features, radiotherapy (RT), and symptom outcomes in cancer patients with cranial nerve palsies associated with clival metastases. PATIENTS AND METHODS: This is a retrospective review of patients with primary metastatic cancers who developed clival metastases and received RT (2000-2020). RESULTS: Of the 44 patients with primary cancers (manly breast, prostate and multiple myeloma cancers) and distal clival metastases, 32 patients (73%) also had cervical spine metastases. Of the 23 RT-treated patients, 65% and 35% received clivus only and whole brain RT, respectively. Post-RT symptom improvement was observed in patients with diplopia (5/6; 83%), headache (8/10; 80%), chin numbness (2/4; 50%), blurry vision (2/5; 40%), lateral gaze deficit (2/6; 33%), and tongue deviation (1/4; 25%). CONCLUSION: Early detection and cranial nerve examination, in addition to RT treatment, should be considered in patients with breast, prostate, and multiple myeloma cancers, who developed cervical spine metastases.


Assuntos
Fossa Craniana Posterior/patologia , Neoplasias/patologia , Neoplasias da Base do Crânio/secundário , Avaliação de Sintomas/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Fossa Craniana Posterior/efeitos da radiação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/radioterapia , Prognóstico , Estudos Retrospectivos , Neoplasias da Base do Crânio/radioterapia , Taxa de Sobrevida
8.
Int J Mol Sci ; 22(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34638817

RESUMO

Local radiotherapy (RT) is important to manage metastatic triple-negative breast cancer (TNBC). Although RT primarily reduces cancer cells locally, this control can be enhanced by triggering the immune system via immunotherapy. RT and immunotherapy may lead to an improved systemic effect, known as the abscopal effect. Here, we analyzed the antitumor effect of combination therapy using RT with an anti-programmed cell death-1 (PD-1) antibody in primary tumors, using poorly immunogenic metastatic mouse mammary carcinoma 4T1 model. Mice were injected subcutaneously into both flanks with 4T1 cells, and treatment was initiated 12 days later. Mice were randomly assigned to three treatment groups: (1) control (no treatment with RT or immune checkpoint inhibitor (ICI)), (2) RT alone, and (3) RT+ICI. The same RT dose was prescribed in both RT-alone and RT+ICI groups as 10Gy/fx in two fractions and delivered to only one of the two tumor burdens injected at both sides of flanks. In the RT+ICI group, 200 µg fixed dose of PD-1 antibody was intraperitoneally administered concurrently with RT. The RT and ICI combination markedly reduced tumor cell growth not only in the irradiated site but also in non-irradiated sites, a typical characteristic of the abscopal effect. This was observed only in radiation-sensitive cancer cells. Lung metastasis development was lower in RT-irradiated groups (RT-only and RT+ICI groups) than in the non-irradiated group, regardless of the radiation sensitivity of tumor cells. However, there was no additive effect of ICI on RT to control lung metastasis, as was already known regarding the abscopal effect. The combination of local RT with anti-PD-1 blockade could be a promising treatment strategy against metastatic TNBC. Further research is required to integrate our results into a clinical setting.


Assuntos
Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias Pulmonares/prevenção & controle , Neoplasias Mamárias Experimentais/terapia , Tolerância a Radiação/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Feminino , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Tolerância a Radiação/imunologia , Tolerância a Radiação/efeitos da radiação
9.
Int J Mol Sci ; 22(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34639063

RESUMO

Autophagy is involved in the degradation of melanosomes and the determination of skin color. TLR4 and tumor necrosis factor (TNF) signaling upregulates NF-kB expression, which is involved in the upregulation of mTOR. The activation of mTOR by UV-B exposure results in decreased autophagy, whereas radiofrequency (RF) irradiation decreases TLR4 and TNF receptor (TNFR) expression. We evaluated whether RF decreased skin pigmentation by restoring autophagy by decreasing the expression of TLR4 or TNFR/NF-κB/mTOR in the UV-B-irradiated animal model. UV-B radiation induced the expressions of TNFR, TLR, and NF-κB in the skin, which were all decreased by RF irradiation. RF irradiation also decreased phosphorylated mTOR expression and upregulated autophagy initiation factors such as FIP200, ULK1, ULK2, ATG13, and ATG101 in the UV-B-irradiated skin. Beclin 1 expression and the expression ratio of LC3-I to LC3-II were increased by UV-B/RF irradiation. Furthermore, melanin-containing autophagosomes increased with RF irradiation. Fontana-Masson staining showed that the amount of melanin deposition in the skin was decreased by RF irradiation. This study showed that RF irradiation decreased skin pigmentation by restoring melanosomal autophagy, and that the possible signal pathways which modulate autophagy could be TLR4, TNFR, NF-κB, and mTOR.


Assuntos
Autofagia/efeitos da radiação , Melaninas/biossíntese , Melanossomas/metabolismo , Ondas de Rádio , Pigmentação da Pele/efeitos da radiação , Raios Ultravioleta , Biomarcadores , Células Cultivadas , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Imuno-Histoquímica , NF-kappa B/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Pigmentação da Pele/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Receptor 4 Toll-Like/metabolismo
10.
Int J Mol Sci ; 22(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34639000

RESUMO

Vitamin D plays an important role in maintaining a healthy mineralized skeleton. It is also considered an immunomodulatory agent that regulates innate and adaptive immune systems. The aim of this narrative review is to provide general concepts of vitamin D for the skeletal and immune health, and to summarize the mechanistic, epidemiological, and clinical evidence on the relationship between vitamin D and rheumatic diseases. Multiple observational studies have demonstrated the association between a low level of serum 25-hydroxyvitamin D [25(OH)D] and the presence and severity of several rheumatic diseases, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), spondyloarthropathies, and osteoarthritis (OA). Nevertheless, the specific benefits of vitamin D supplements for the treatment and prevention of rheumatic diseases are less accepted as the results from randomized clinical trials are inconsistent, although some conceivable benefits of vitamin D for the improvement of disease activity of RA, SLE, and OA have been demonstrated in meta-analyses. It is also possible that some individuals might benefit from vitamin D differently than others, as inter-individual difference in responsiveness to vitamin D supplementation has been observed in genomic studies. Although the optimal level of serum 25(OH)D is still debatable, it is advisable it is advisable that patients with rheumatic diseases should maintain a serum 25(OH)D level of at least 30 ng/mL (75 nmol/L) to prevent osteomalacia, secondary osteoporosis, and fracture, and possibly 40-60 ng/mL (100-150 nmol/L) to achieve maximal benefit from vitamin D for immune health and overall health.


Assuntos
Suscetibilidade a Doenças , Doenças Reumáticas/etiologia , Doenças Reumáticas/metabolismo , Vitamina D/metabolismo , Biomarcadores , Gerenciamento Clínico , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Lúpus Eritematoso Sistêmico/etiologia , Lúpus Eritematoso Sistêmico/metabolismo , Redes e Vias Metabólicas/efeitos da radiação , Músculo Esquelético/metabolismo , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/tratamento farmacológico , Luz Solar , Resultado do Tratamento , Vitamina D/análogos & derivados , Vitamina D/uso terapêutico , Deficiência de Vitamina D/complicações
11.
Int J Mol Sci ; 22(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34639012

RESUMO

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood. About 25% of RMS expresses fusion oncoproteins such as PAX3/PAX7-FOXO1 (fusion-positive, FP) while fusion-negative (FN)-RMS harbors RAS mutations. Radiotherapy (RT) plays a crucial role in local control but metastatic RMS is often radio-resistant. HDAC inhibitors (HDACi) radio-sensitize different cancer cells types. Thus, we evaluated MS-275 (Entinostat), a Class I and IV HDACi, in combination with RT on RMS cells in vitro and in vivo. MS-275 reversibly hampered cell survival in vitro in FN-RMS RD (RASmut) and irreversibly in FP-RMS RH30 cell lines down-regulating cyclin A, B, and D1, up-regulating p21 and p27 and reducing ERKs activity, and c-Myc expression in RD and PI3K/Akt/mTOR activity and N-Myc expression in RH30 cells. Further, MS-275 and RT combination reduced colony formation ability of RH30 cells. In both cell lines, co-treatment increased DNA damage repair inhibition and reactive oxygen species formation, down-regulated NRF2, SOD, CAT and GPx4 anti-oxidant genes and improved RT ability to induce G2 growth arrest. MS-275 inhibited in vivo growth of RH30 cells and completely prevented the growth of RT-unresponsive RH30 xenografts when combined with radiation. Thus, MS-275 could be considered as a radio-sensitizing agent for the treatment of intrinsically radio-resistant PAX3-FOXO1 RMS.


Assuntos
Benzamidas/farmacologia , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição Box Pareados/genética , Piridinas/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/genética , Radiossensibilizantes/farmacologia , Rabdomiossarcoma/genética , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Rabdomiossarcoma/metabolismo , Rabdomiossarcoma/radioterapia
12.
Int J Mol Sci ; 22(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34639030

RESUMO

During the cell cycle, DNA suffers several lesions that need to be repaired prior to entry into mitosis to preserve genome integrity in daughter cells. Toward this aim, cells have developed complex enzymatic machinery, the so-called DNA damage response (DDR), which is able to repair DNA, temporarily stopping the cell cycle to provide more time to repair, or if the damage is too severe, inducing apoptosis. This DDR mechanism is considered the main source of resistance to DNA-damaging therapeutic treatments in oncology. Recently, cancer stem cells (CSCs), which are a small subset of tumor cells, were identified as tumor-initiating cells. CSCs possess self-renewal potential and persistent tumorigenic capacity, allowing for tumor re-growth and relapse. Compared with cancer cells, CSCs are more resistant to therapeutic treatments. Wee1 is the principal gatekeeper for both G2/M and S-phase checkpoints, where it plays a key role in cell cycle regulation and DNA damage repair. From this perspective, Wee1 inhibition might increase the effectiveness of DNA-damaging treatments, such as radiotherapy, forcing tumor cells and CSCs to enter into mitosis, even with damaged DNA, leading to mitotic catastrophe and subsequent cell death.


Assuntos
Biomarcadores Tumorais , Proteínas de Ciclo Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Tirosina Quinases/genética , Tolerância a Radiação/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Terapia Combinada , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular , Família Multigênica , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Especificidade de Órgãos/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo
13.
Int J Mol Sci ; 22(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34638618

RESUMO

Wildlife is chronically exposed to various sources of ionizing radiations, both environmental or anthropic, due to nuclear energy use, which can induce several defects in organisms. In invertebrates, reproduction, which directly impacts population dynamics, has been found to be the most radiosensitive endpoint. Understanding the underlying molecular pathways inducing this reproduction decrease can help in predicting the effects at larger scales (i.e., population). In this study, we used a life stage dependent approach in order to better understand the molecular determinants of reproduction decrease in the roundworm C. elegans. Worms were chronically exposed to 50 mGy·h-1 external gamma ionizing radiations throughout different developmental periods (namely embryogenesis, gametogenesis, and full development). Then, in addition to reproduction parameters, we performed a wide analysis of lipids (different class and fatty acid via FAMES), which are both important signaling molecules for reproduction and molecular targets of oxidative stress. Our results showed that reproductive defects are life stage dependent, that lipids are differently misregulated according to the considered exposure (e.g., upon embryogenesis and full development) and do not fully explain radiation induced reproductive defects. Finally, our results enable us to propose a conceptual model of lipid signaling after radiation stress in which both the soma and the germline participate.


Assuntos
Caenorhabditis elegans/efeitos da radiação , Metabolismo dos Lipídeos/efeitos da radiação , Reprodução/efeitos da radiação , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/fisiologia , Ácidos Graxos/metabolismo , Feminino , Raios gama/efeitos adversos , Masculino , Modelos Biológicos , Estresse Oxidativo/efeitos da radiação , Tolerância a Radiação , Reprodução/fisiologia
14.
ACS Appl Mater Interfaces ; 13(42): 49754-49761, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34657424

RESUMO

A reliable and sensitive detection approach for SARS-CoV 2 is essential for timely infection diagnosis and transmission prevention. Here, a two-dimensional (2D) metal-organic framework (MOF)-based photoelectrochemical (PEC) aptasensor with high sensitivity and stability for SARS-CoV 2 spike glycoprotein (S protein) detection was developed. The PEC aptasensor was constructed by a plasmon-enhanced photoactive material (namely, Au NPs/Yb-TCPP) with a specific DNA aptamer against S protein. The Au NPs/Yb-TCPP fabricated by in situ growth of Au NPs on the surface of 2D Yb-TCPP nanosheets showed a high electron-hole (e-h) separation efficiency due to the enhancement effect of plasmon, resulting in excellent photoelectric performance. The modified DNA aptamer on the surface of Au NPs/Yb-TCPP can bind with S protein with high selectivity, thus decreasing the photocurrent of the system due to the high steric hindrance and low conductivity of the S protein. The established PEC aptasensor demonstrated a highly sensitive detection for S protein with a linear response range of 0.5-8 µg/mL with a detection limit of 72 ng/mL. This work presented a promising way for the detection of SARS-CoV 2, which may conduce to the impetus of clinic diagnostics.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Estruturas Metalorgânicas/química , SARS-CoV-2/química , Glicoproteína da Espícula de Coronavírus/análise , Sequência de Bases , Técnicas Biossensoriais/instrumentação , COVID-19/diagnóstico , DNA/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Ouro/efeitos da radiação , Humanos , Ácidos Nucleicos Imobilizados/química , Luz , Limite de Detecção , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Faringe/virologia , Processos Fotoquímicos , Porfirinas/química , Glicoproteína da Espícula de Coronavírus/química , Itérbio/química
15.
PLoS One ; 16(10): e0257605, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34648511

RESUMO

The objective of this study is to develop a skeleton model for assessing active marrow dose from bone-seeking beta-emitting radionuclides. This article explains the modeling methodology which accounts for individual variability of the macro- and microstructure of bone tissue. Bone sites with active hematopoiesis are assessed by dividing them into small segments described by simple geometric shapes. Spongiosa, which fills the segments, is modeled as an isotropic three-dimensional grid (framework) of rod-like trabeculae that "run through" the bone marrow. Randomized multiple framework deformations are simulated by changing the positions of the grid nodes and the thickness of the rods. Model grid parameters are selected in accordance with the parameters of spongiosa microstructures taken from the published papers. Stochastic modeling of radiation transport in heterogeneous media simulating the distribution of bone tissue and marrow in each of the segments is performed by Monte Carlo methods. Model output for the human femur at different ages is provided as an example. The uncertainty of dosimetric characteristics associated with individual variability of bone structure was evaluated. An advantage of this methodology for the calculation of doses absorbed in the marrow from bone-seeking radionuclides is that it does not require additional studies of autopsy material. The biokinetic model results will be used in the future to calculate individual doses to members of a cohort exposed to 89,90Sr from liquid radioactive waste discharged to the Techa River by the Mayak Production Association in 1949-1956. Further study of these unique cohorts provides an opportunity to gain more in-depth knowledge about the effects of chronic radiation on the hematopoietic system. In addition, the proposed model can be used to assess the doses to active marrow under any other scenarios of 90Sr and 89Sr intake to humans.


Assuntos
Partículas beta/efeitos adversos , Medula Óssea/efeitos da radiação , Osso e Ossos/efeitos da radiação , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Simulação por Computador , Feminino , Hematopoese/efeitos da radiação , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Método de Monte Carlo , Doses de Radiação , Radiometria , Processos Estocásticos , Adulto Jovem
16.
Cancer Treat Rev ; 101: 102297, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34656018

RESUMO

Introduction of sentinel lymph node biopsy, initially in clinically node-negative and subsequently in patients presenting with involved axilla and downstaged by primary systemic therapy, allowed for significant decrease in morbidity compared to axillary lymph node dissection. Concurrently, regional nodal irradiation was demonstrated to improve outcomes in most node-positive patients. Additionally, over the last decades, introduction of more effective systemic therapies has resulted in improvements not only at distant sites, but also in locoregional control, creating space for de-escalation of locoregional treatments. We discuss the data on de-escalation in axillary surgery and irradiation, both in patients undergoing upfront surgery and primary systemic therapy, with special emphasis on the feasibility of omission of nodal irradiation in patients undergoing primary systemic therapy. In view of the accumulating evidence, omission of axillary irradiation may be considered in clinically node-positive patients converting after primary systemic therapy to pathologically negative nodes on sentinel lymph node biopsy (preferably also with in-breast pCR), presenting with lower initial nodal stage, older age and were treated with breast-conserving surgery followed by whole breast irradiation. Omission of regional nodal irradiation in patients with aggressive tumor phenotypes achieving a pCR is under investigation. In patients undergoing preoperative endocrine therapy the adoption of axillary management strategies utilized in case of upfront surgery seems more suitable than those used in post chemotherapy-based primary systemic therapy setting.


Assuntos
Neoplasias da Mama , Linfonodos , Protocolos Antineoplásicos , Axila , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Terapia Combinada , Humanos , Excisão de Linfonodo/métodos , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Linfonodos/efeitos da radiação , Linfonodos/cirurgia , Irradiação Linfática/métodos , Estadiamento de Neoplasias , Biópsia de Linfonodo Sentinela
17.
Nutrients ; 13(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34684482

RESUMO

Sleep is an essential component of overall human health but is so tightly regulated that when disrupted can cause or worsen certain ailments. An important part of this process is the presence of the well-known hormone, melatonin. This compound assists in the governing of sleep and circadian rhythms. Previous studies have postulated that dysregulation of melatonin rhythms is the driving force behind sleep and circadian disorders. A computer-aided search spanning the years of 2015-2020 using the search terms melatonin, circadian rhythm, disorder yielded 52 full text articles that were analyzed. We explored the mechanisms behind melatonin dysregulation and how it affects various disorders. Additionally, we examined associated therapeutic treatments including bright light therapy (BLT) and exogenous forms of melatonin. We found that over the past 5 years, melatonin has not been widely investigated in clinical studies thus there remains large gaps in its potential utilization as a therapy.


Assuntos
Ritmo Circadiano/fisiologia , Melatonina/metabolismo , Animais , Vias Biossintéticas , Ritmo Circadiano/efeitos da radiação , Humanos , Luz , Melatonina/biossíntese , Melatonina/química , Transcrição Genética
18.
BMC Plant Biol ; 21(1): 478, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34670494

RESUMO

BACKGROUND: Catechins are crucial in determining the flavour and health benefits of tea, but it remains unclear that how the light intensity regulates catechins biosynthesis. Therefore, we cultivated tea plants in a phytotron to elucidate the response mechanism of catechins biosynthesis to light intensity changes. RESULTS: In the 250 µmol·m- 2·s- 1 treatment, the contents of epigallocatechin, epigallocatechin gallate and total catechins were increased by 98.94, 14.5 and 13.0% respectively, compared with those in the 550 µmol·m- 2·s- 1 treatment. Meanwhile, the photosynthetic capacity was enhanced in the 250 µmol·m- 2·s- 1 treatment, including the electron transport rate, net photosynthetic rate, transpiration rate and expression of related genes (such as CspsbA, CspsbB, CspsbC, CspsbD, CsPsbR and CsGLK1). In contrast, the extremely low or high light intensity decreased the catechins accumulation and photosynthetic capacity of the tea plants. The comprehensive analysis revealed that the response of catechins biosynthesis to the light intensity was mediated by the photosynthetic capacity of the tea plants. Appropriately high light upregulated the expression of genes related to photosynthetic capacity to improve the net photosynthetic rate (Pn), transpiration rate (Tr), and electron transfer rate (ETR), which enhanced the contents of substrates for non-esterified catechins biosynthesis (such as EGC). Meanwhile, these photosynthetic capacity-related genes and gallic acid (GA) biosynthesis-related genes (CsaroB, CsaroDE1, CsaroDE2 and CsaroDE3) co-regulated the response of GA accumulation to light intensity. Eventually, the epigallocatechin gallate content was enhanced by the increased contents of its precursors (EGC and GA) and the upregulation of the CsSCPL gene. CONCLUSIONS: In this study, the catechin content and photosynthetic capacity of tea plants increased under appropriately high light intensities (250 µmol·m- 2·s- 1 and 350 µmol·m- 2·s- 1) but decreased under extremely low or high light intensities (150 µmol·m- 2·s- 1 or 550 µmol·m- 2·s- 1). We found that the control of catechin accumulation by light intensity in tea plants is mediated by the plant photosynthetic capacity. The research provided useful information for improving catechins content and its light-intensity regulation mechanism in tea plant.


Assuntos
Camellia sinensis/efeitos da radiação , Catequina/análogos & derivados , Catequina/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Fotossíntese/efeitos da radiação , Proteínas de Plantas/metabolismo , Camellia sinensis/genética , Camellia sinensis/fisiologia , Catequina/efeitos da radiação , Luz , Proteínas de Plantas/genética , Plântula/genética , Plântula/fisiologia , Plântula/efeitos da radiação , Regulação para Cima
19.
PLoS Comput Biol ; 17(10): e1009474, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34662342

RESUMO

The role of heating, ventilation, and air-conditioning (HVAC) systems in the transmission of SARS-CoV-2 is unclear. To address this gap, we simulated the release of SARS-CoV-2 in a multistory office building and three social gathering settings (bar/restaurant, nightclub, wedding venue) using a well-mixed, multi-zone building model similar to those used by Wells, Riley, and others. We varied key factors of HVAC systems, such as the Air Changes Per Hour rate (ACH), Fraction of Outside Air (FOA), and Minimum Efficiency Reporting Values (MERV) to examine their effect on viral transmission, and additionally simulated the protective effects of in-unit ultraviolet light decontamination (UVC) and separate in-room air filtration. In all building types, increasing the ACH reduced simulated infections, and the effects were seen even with low aerosol emission rates. However, the benefits of increasing the fraction of outside air and filter efficiency rating were greatest when the aerosol emission rate was high. UVC filtration improved the performance of typical HVAC systems. In-room filtration in an office setting similarly reduced overall infections but worked better when placed in every room. Overall, we found little evidence that HVAC systems facilitate SARS-CoV-2 transmission; most infections in the simulated office occurred near the emission source, with some infections in individuals temporarily visiting the release zone. HVAC systems only increased infections in one scenario involving a marginal increase in airflow in a poorly ventilated space, which slightly increased the likelihood of transmission outside the release zone. We found that improving air circulation rates, increasing filter MERV rating, increasing the fraction of outside air, and applying UVC radiation and in-room filtration may reduce SARS-CoV-2 transmission indoors. However, these mitigation measures are unlikely to provide a protective benefit unless SARS-CoV-2 aerosol emission rates are high (>1,000 Plaque-forming units (PFU) / min).


Assuntos
Ar Condicionado , COVID-19/transmissão , Calefação , SARS-CoV-2 , Ventilação , Aerossóis , Microbiologia do Ar , Movimentos do Ar , COVID-19/prevenção & controle , COVID-19/virologia , Biologia Computacional , Simulação por Computador , Humanos , Modelos Biológicos , Pandemias , SARS-CoV-2/efeitos da radiação , Interação Social , Raios Ultravioleta , Local de Trabalho
20.
Medicine (Baltimore) ; 100(42): e27155, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34678859

RESUMO

ABSTRACT: The focus of this prospective cohort study was to evaluate the risk factors of severe acute skin toxicity (grade ≥2) in 100 patients with breast cancer (BC) during radiotherapy (RT).The patients were evaluated weekly during RT and 3 months after treatment. The endpoint included the occurrence of skin toxicity grade ≥2, according to Radiation Therapy Oncology Group (RTOG). Survival analysis was conducted by univariate and multivariate Cox regression analysis.In the multivariate analysis, RT in the afternoon (0-3 pm) (hazard ratios [HR] = 1.566, P = .042) was significantly associated with the early occurrence of skin toxicity, indicating a potential effect of chronotherapy related to this adverse event. In the univariate and multivariate analysis, skin phototype moderate brown (HR = 1.586, P = .042; HR = 1.706, P = .022, respectively) and dark brown or black (HR = 4.517, P < .001; HR = 5.336, P < 0.001, respectively) was significantly associated with the skin toxicity. Tangential field separation >21 cm (HR = 2.550, P = .009, HR = 2.923, P = .003), in women that were submitted to conservative surgery indicates indirectly that large breast size was also significantly associated with skin toxicity.Women with large breasts and dark brown or black skin should be followed more carefully during RT, which should be undergone in the morning, especially when submitted to conventional RT techniques, common in developing countries.


Assuntos
Neoplasias da Mama/radioterapia , Dermatite/etiologia , Dermatite/prevenção & controle , Lesões por Radiação/prevenção & controle , Idoso , Índice de Massa Corporal , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Hospitais Universitários , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Fatores de Risco , Pele/efeitos da radiação , Fatores Socioeconômicos
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