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1.
J Am Chem Soc ; 146(15): 10251-10256, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38587307

RESUMO

While the shape-dependent quantum confinement (QC) effect in anisotropic semiconductor nanocrystals has been extensively studied, the QC in facet-specified polyhedral quantum dots (QDs) remains underexplored. Recently, tetrahedral nanocrystals have gained prominence in III-V nanocrystal synthesis. In our study, we successfully synthesized well-faceted tetrahedral InAs QDs with a first excitonic absorption extending up to 1700 nm. We observed an unconventional sizing curve, indicating weaker confinement than for equivalently volumed spherical QDs. The (111) surface states of InAs QDs persist at the conduction band minimum state even after ligand passivation with a significantly reduced band gap, which places tetrahedral QDs at lower energies in the sizing curve. Consequently, films composed of tetrahedral QDs demonstrate an extended photoresponse into the short-wave infrared region, compared to isovolume spherical QD films.

2.
Diabetes Obes Metab ; 26(6): 2248-2256, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38456558

RESUMO

AIM: To evaluate the long-term safety and efficacy of enavogliflozin 0.3 mg/day added to metformin in patients with type 2 diabetes mellitus. MATERIALS AND METHODS: After 24 weeks of a randomized, double-blind treatment period with enavogliflozin 0.3 mg/day (n = 101) or dapagliflozin 10 mg/day (n = 99) added to metformin, all patients received enavogliflozin 0.3 mg/day plus metformin for an additional 28 weeks during the open-label extension period. RESULTS: Eighty-two patients continued enavogliflozin (maintenance group), and 77 were switched from dapagliflozin to enavogliflozin (switch group). All adverse drug reactions (ADR) were mild in severity. In the maintenance group, ADRs (cystitis and vaginal infection) were reported in two patients (2.44%) during 52 weeks. In the switch group, ADR (hypoglycaemia) was reported in one patient (1.30%) during a 28-week open-label extension period. At week 52, glycated haemoglobin and fasting plasma glucose were significantly lower than at the baseline, by 0.85% and 29.08 mg/dl, respectively, in the maintenance group (p < .0001 for both), and by 0.81% and 32.77 mg/dl, respectively, in the switch group (p < .0001 for both). At week 52, 68.92% of patients from the maintenance group and 64.29% from the switch group achieved glycated haemoglobin <7%. A significant increase in the urine glucose-creatinine ratio was observed at week 52, by 58.81 g/g and 63.77 g/g in the maintenance and switch groups, respectively (p < .0001). CONCLUSIONS: Enavogliflozin added to metformin was tolerated well for up to 52 weeks and provided continual glycaemic control in type 2 diabetes mellitus, along with a significant increase in the urine glucose-creatinine ratio.


Assuntos
Compostos Benzidrílicos , Glicemia , Diabetes Mellitus Tipo 2 , Quimioterapia Combinada , Glucosídeos , Hemoglobinas Glicadas , Hipoglicemiantes , Metformina , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Compostos Benzidrílicos/efeitos adversos , Compostos Benzidrílicos/uso terapêutico , Glucosídeos/efeitos adversos , Glucosídeos/uso terapêutico , Glucosídeos/administração & dosagem , Metformina/efeitos adversos , Metformina/uso terapêutico , Metformina/administração & dosagem , Feminino , Pessoa de Meia-Idade , Masculino , Quimioterapia Combinada/efeitos adversos , Método Duplo-Cego , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/administração & dosagem , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Hemoglobinas Glicadas/efeitos dos fármacos , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Idoso , Resultado do Tratamento , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Hipoglicemia/induzido quimicamente , Hipoglicemia/epidemiologia , Adulto , Benzofuranos
3.
Nucleic Acids Res ; 50(16): 9247-9259, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-35979947

RESUMO

Cells are constantly challenged by genotoxic stresses that can lead to genome instability. The integrity of the nuclear genome is preserved by the DNA damage response (DDR) and repair. Additionally, these stresses can induce mitochondria to transiently hyperfuse; however, it remains unclear whether canonical DDR is linked to these mitochondrial morphological changes. Here, we report that the abolition of mitochondrial fusion causes a substantial defect in the ATM-mediated DDR signaling. This deficiency is overcome by the restoration of mitochondria fusion. In cells with fragmented mitochondria, genotoxic stress-induced activation of JNK and its translocation to DNA lesion are lost. Importantly, the mitochondrial fusion machinery of MFN1/MFN2 associates with Sab (SH3BP5) and JNK, and these interactions are indispensable for the Sab-mediated activation of JNK and the ATM-mediated DDR signaling. Accordingly, the formation of BRCA1 and 53BP1 foci, as well as homology and end-joining repair are impaired in cells with fragmented mitochondria. Together, these data show that mitochondrial fusion-dependent JNK signaling is essential for the DDR, providing vital insight into the integration of nuclear and cytoplasmic stress signals.


Assuntos
Dano ao DNA , Reparo do DNA , Humanos , Reparo do DNA/genética , Instabilidade Genômica , Mitocôndrias/genética , Transdução de Sinais/genética
4.
Environ Toxicol ; 39(4): 2304-2315, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38148711

RESUMO

Cigarette smoke induces an inflammatory response in the lungs by recruiting inflammatory cells, leading to lung diseases such as lung cancer, chronic obstructive pulmonary disease, and pulmonary fibrosis. Existing inhalation exposure methods for assessing the adverse effects of cigarette smoke require expensive equipment and are labor-intensive. Therefore, we attempted to develop a novel method to assess these adverse effects using intratracheal instillation (ITI) of whole cigarette smoke condensate (WCSC). The WCSC (0, 5, 10, or 20 mg/mL) was administered by ITI once daily for 6 or 12 days using an automatic video instillator. Repeated WCSC ITI increased the lung weight, and monocyte chemoattractant protein-1 (MCP-1), neutrophil, and lymphocyte levels within bronchoalveolar lavage fluid compared to the control. In the histopathological analysis of the lung tissue, a mild inflammatory response was observed in the 6 and 12 days 20 mg/mL WCSC exposure groups. The genome-wide RNA-seq expression patterns revealed that inflammatory and immune response-related genes, such as the chemokine signaling pathway, Th1/Th2 cell differentiation, and cytokine-cytokine receptor interaction, were employed following WCSC exposure. In addition, MCP-1 was time-dependent and increased in the 10 mg/mL exposure group compared to the control group. These results suggested that the WCSC might induce the potential pulmonary inflammatory response. Furthermore, we proposed that ITI may be a rapid and effective method of evaluating the adverse effects of WCSC within a short exposure period (less than 2 weeks), and it can be used to evaluate cigarette inhalation toxicity studies as an alternative method.


Assuntos
Fumar Cigarros , Pneumopatias , Doença Pulmonar Obstrutiva Crônica , Ratos , Animais , Pulmão , Doença Pulmonar Obstrutiva Crônica/metabolismo , Pneumopatias/patologia , Líquido da Lavagem Broncoalveolar
5.
Small ; 19(47): e2302713, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37485739

RESUMO

The fundamental aspects of energy dissipation on 2-dimensional (2D) atomic layers are extensively studied. Among various atomic layers, transition metal dichalcogenides (TMDs) exists in several phases based on their lattice structure, which give rise to the different phononic and electronic contributions in energy dissipation. 2H and 1T' (distorted 1T) phase MoS2 and MoTe2 atomic layers exfoliated on mica substrate are obtained and investigated their nanotribological properties with atomic force microscopy (AFM)/ friction force microscopy (FFM). Surprisingly, 1T' phase of both MoS2 and MoTe2 exhibits ≈10 times higher friction compared to 2H phase. With density functional theory analyses, the friction increase is attributed to enhanced electronic excitation, efficient phonon dissipation, and increased potential energy surface barrier at the tip-sample interface. This study suggests the intriguing possibility of tuning the friction of TMDs through phase transition, which can lead to potential application in tunable tribological devices.

6.
Ecotoxicol Environ Saf ; 256: 114915, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37079939

RESUMO

An increase in the concentration of environmental particulate matter and the spread of the COVID-19 virus have dramatically increased our time spent wearing masks. If harmful chemicals are released from these masks, there may be harmful effects on human health. In this study, the concentration of volatile organic compounds (VOCs) emitted from some commonly used masks was assessed qualitatively and quantitatively under diverse conditions (including different mask material types, time between opening the product and wearing, and mask temperature). In KF94 masks, 1-methoxy-2-propanol (221 ± 356 µg m-3), N,N-dimethylacetamide (601 ± 450 µg m-3), n-hexane (268 ± 349 µg m-3), and 2-butanone (160 ± 244 µg m-3) were detected at concentrations 22.9-147 times higher than those found in masks made from other materials, such as cotton and other functional fabrics. In addition, in KF94 masks, the total VOC (TVOC) released amounted to 3730 ± 1331 µg m-3, about 14 times more than that released by the cotton masks (267.5 ± 51.6 µg m-3). In some KF94 masks, TVOC concentration reached over 4000 µg m-3, posing a risk to human health (based on indoor air quality guidelines established by the German Environment Agency). Notably, 30 min after KF94 masks were removed from their packaging, TVOC concentrations decreased by about 80% from their initial levels to 724 ± 5.86 µg m-3; furthermore, 6 h after removal, TVOC concentrations were found to be less than 200 µg m-3. When the temperature of the KF94 masks was raised to 40 oC, TVOC concentrations increased by 119-299%. Since the types and concentrations of VOCs that will be inhaled by mask wearers vary depending on the mask use conditions, it is necessary to comply with safe mask wearing conditions.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Máscaras , Poluição do Ar em Ambientes Fechados/análise , Material Particulado , Monitoramento Ambiental
7.
Ecotoxicol Environ Saf ; 267: 115621, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37879201

RESUMO

A method of preparing heated tobacco product aerosol condensate (HTPAC) was developed to expedite HTP toxicity evaluation, and the effectiveness was assessed. To prepare HTPAC, HTP aerosol was generated and collected using a Cambridge filter (particulate phase) and Dulbecco's phosphate buffered saline (DPBS; gaseous phase). The aerosol collected on the Cambridge filter was extracted using methanol, which was thereafter removed by nitrogen purging. The HTP aerosol residue was mixed with DPBS loaded with the collected HTP vapor, ultimately yielding HTPAC. Nicotine and formaldehyde, key harmful compounds in HTP aerosol, were detected in HTPAC (901 ± 224 and 22.2 ± 3.90 µg stick-1, respectively, comparable to those in HTP aerosol (990-1350 (nicotine) and 2.33-21.9 µg stick-1 (formaldehyde)). Propylene glycol and vegetable glycerin, which influence the amount of HTP aerosol, were detected at similar levels in HTPAC and HTP aerosol (propylene glycol = 616 ± 57.1 (HTPAC) and 320-630 µg stick-1 (aerosol) and vegetable glycerin = 2418 ± 224 (HTPAC) and 1667-4000 µg stick-1 (aerosol)). Known components of HTP aerosol (hydroxyacetone, acetic acid, triacetin, and 2-furanmethanol) were also detected in HTPAC. Consequently, HTPAC offers an effective method for concentrating harmful compounds found in HTP aerosols. This, in turn, facilitates comprehensive toxicity assessments, paving the way for guidelines ensuring the safe utilization of HTP.


Assuntos
Glicerol , Produtos do Tabaco , Nicotina , Aerossóis , Formaldeído , Gases , Propilenoglicol
8.
Int J Mol Sci ; 24(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36983054

RESUMO

Protic ruthenium complexes using the dihydroxybipyridine (dhbp) ligand combined with a spectator ligand (N,N = bpy, phen, dop, Bphen) have been studied for their potential activity vs. cancer cells and their photophysical luminescent properties. These complexes vary in the extent of π expansion and the use of proximal (6,6'-dhbp) or distal (4,4'-dhbp) hydroxy groups. Eight complexes are studied herein as the acidic (OH bearing) form, [(N,N)2Ru(n,n'-dhbp)]Cl2, or as the doubly deprotonated (O- bearing) form. Thus, the presence of these two protonation states gives 16 complexes that have been isolated and studied. Complex 7A, [(dop)2Ru(4,4'-dhbp)]Cl2, has been recently synthesized and characterized spectroscopically and by X-ray crystallography. The deprotonated forms of three complexes are also reported herein for the first time. The other complexes studied have been synthesized previously. Three complexes are light-activated and exhibit photocytotoxicity. The log(Do/w) values of the complexes are used herein to correlate photocytotoxicity with improved cellular uptake. For Ru complexes 1-4 bearing the 6,6'-dhbp ligand, photoluminescence studies (all in deaerated acetonitrile) have revealed that steric strain leads to photodissociation which tends to reduce photoluminescent lifetimes and quantum yields in both protonation states. For Ru complexes 5-8 bearing the 4,4'-dhbp ligand, the deprotonated Ru complexes (5B-8B) have low photoluminescent lifetimes and quantum yields due to quenching that is proposed to involve the 3LLCT excited state and charge transfer from the [O2-bpy]2- ligand to the N,N spectator ligand. The protonated OH bearing 4,4'-dhbp Ru complexes (5A-8A) have long luminescence lifetimes which increase with increasing π expansion on the N,N spectator ligand. The Bphen complex, 8A, has the longest lifetime of the series at 3.45 µs and a photoluminescence quantum yield of 18.7%. This Ru complex also exhibits the best photocytotoxicity of the series. A long luminescence lifetime is correlated with greater singlet oxygen quantum yields because the triplet excited state is presumably long-lived enough to interact with 3O2 to yield 1O2.


Assuntos
Luminescência , Rutênio , Rutênio/química , Ligantes
9.
J Am Chem Soc ; 144(22): 10025-10033, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35616519

RESUMO

Noncrystalline oxides under pressure undergo gradual structural modifications, highlighted by the formation of a dense noncrystalline network topology. The nature of the densified networks and their electronic structures at high pressures may account for the mechanical hardening and the anomalous changes in electromagnetic properties. Despite its importance, direct probing of the electronic structures in amorphous oxides under compression above the Mbar pressure (>100 GPa) is currently lacking. Here, we report the observation of pressure-driven changes in electronic configurations and their delocalization around oxygen in glasses using inelastic X-ray scattering spectroscopy (IXS). In particular, the first O K-edge IXS spectra for compressed GeO2 glass up to 148 GPa, the highest pressure ever reached in an experimental study of GeO2 glass, reveal that the glass densification results from a progressive increase of oxygen proximity. While the triply coordinated oxygen [3]O is dominant below ∼50 GPa, the IXS spectra resolve multiple edge features that are unique to topologically disordered [4]O upon densification above 55 GPa. Topological compaction in GeO2 glass above 100 GPa results in pronounced electronic delocalization, revealing the contribution from Ge d-orbitals to oxide densification. Strong correlations between the glass density and the electronic configurations beyond the Mbar conditions highlight the electronic origins of densification of heavy-metal-bearing oxide glasses. Current experimental breakthroughs shed light on the direct probing of the electronic density of states in high-Z oxides above 1 Mbar, offering prospects for studies on the pressure-driven changes in magnetism, superconductivity, and electronic transport properties in heavy-metal-bearing oxides under compression.

10.
Antimicrob Agents Chemother ; 66(2): e0168421, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34871098

RESUMO

Delpazolid, an oxazolidinone, has been studied in non-clinical studies of efficacy and toxicity and Phase 1 clinical studies. Delpazolid has in vitro activity against Gram-positive bacteria, including Mycobacterium tuberculosis. This study evaluated the bactericidal activity, safety, and pharmacokinetics of delpazolid in patients with pulmonary tuberculosis (TB). Seventy-nine subjects, aged 19 to 75 years with newly diagnosed smear-positive TB with no prior treatment for the current episode and no confirmed resistance to rifampin or isoniazid, were randomized to receive delpazolid 800 mg once a day (QD), 400 mg twice a day (BID), 800 mg BID or 1,200 mg QD or an active control of isoniazid, rifampin, pyrazinamide, and ethambutol (HRZE) or linezolid 600 mg BID. The primary endpoint was the average daily reduction in log transformed bacterial load, assessed on 7H11 solid-media culture, from days 0 to 14. The average daily decline in log-CFU was 0.044 ± 0.016, 0.053 ± 0.017, 0.043 ± 0.016, and 0.019 ± 0.017, for the delpazolid 800 mg QD, 400 mg BID, 800 mg BID, and the 1,200 mg QD groups, respectively. The average daily decline in log-CFU was 0.192 ± 0.028 for the HRZE group and 0.154 ± 0.023 for the linezolid 600 mg BID group. Three serious adverse events (SAE) were reported, one each in the delpazolid 400 mg BID group (death due to worsening of TB at day 2), the HRZE group (hospitalization due to pleural effusion) and the linezolid group (hyperkalemia); none of the SAEs were assessed as related to study drugs. This study has been registered at ClinicalTrials.gov with registration number NCT02836483.


Assuntos
Mycobacterium tuberculosis , Oxazolidinonas , Tuberculose Pulmonar , Adulto , Idoso , Antituberculosos/uso terapêutico , Quimioterapia Combinada , Humanos , Isoniazida/uso terapêutico , Pessoa de Meia-Idade , Oxazolidinonas/farmacocinética , Oxazolidinonas/uso terapêutico , Pirazinamida/uso terapêutico , Escarro/microbiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia , Adulto Jovem
11.
Biochem Biophys Res Commun ; 632: 173-180, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36209586

RESUMO

The presence of circulating cancer cells in the bloodstream is positively correlated with metastasis. We hypothesize that fluid shear stress (FSS) occurring during circulation alters mitochondrial function, enhancing metastatic behaviors of cancer cells. MCF7 and MDA-MB-231 human breast cancer cells subjected to FSS exponentially increased proliferation. Notably, FSS-treated cells consumed more oxygen but were resistant to uncoupler-mediated ATP loss. We found that exposure to FSS downregulated the F1FO ATP synthase c-subunit and overexpression of the c-subunit arrested cancer cell migration. Approaches that regulate c-subunit abundance may reduce the likelihood of breast cancer metastasis.


Assuntos
Neoplasias da Mama , ATPases Mitocondriais Próton-Translocadoras , Humanos , Feminino , ATPases Mitocondriais Próton-Translocadoras/genética , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Regulação para Baixo , Trifosfato de Adenosina , Proliferação de Células , Oxigênio
12.
Cardiovasc Diabetol ; 21(1): 245, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36380325

RESUMO

BACKGROUND: Hypertriglyceridemia is an important feature of dyslipidemia in type 1 and type 2 diabetic patients and associated with the development of atherosclerotic cardiovascular disease. Recently, variability of lipid profile has been suggested as a residual risk factor for cardiovascular disease. This study compared the clinical impact of serum triglyceride variability, and their cumulative exposure estimates on cardiovascular prognosis in diabetic patients. METHODS: A total of 25,933 diabetic patients who had serum triglyceride levels measured at least 3 times and did not have underlying malignancy, myocardial infarction (MI), and stroke during the initial 3 years (modeling phase) were selected from three tertiary hospitals. They were divided into a high/low group depending on their coefficient of variation (CV) and cumulative exposure estimate (CEE). Incidence of major adverse event (MAE), a composite of all-cause death, MI, and stroke during the following 5 years were compared between groups by multivariable analysis after propensity score matching. RESULTS: Although there was a slight difference, both the high CV group and the high CEE group had a higher cardiovascular risk profile including male-dominance, smoking, alcohol, dyslipidemia, and chronic kidney disease compared to the low groups. After the propensity score matching, the high CV group showed higher MAE incidence compared to the low CV group (9.1% vs 7.7%, p = 0.01). In contrast, there was no significant difference of MAE incidence between the high CEE group and the low CEE group (8.6% vs 9.1%, p = 0.44). After the multivariable analysis with further adjustment for potential residual confounding factors, the high CV was suggested as an independent risk predictor for MAE (HR 1.19 [95% CI 1.03-1.37]). CONCLUSION: Visit-to-visit variability of triglyceride rather than their cumulative exposure is more strongly related to the incidence of MAE in diabetic patients.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Dislipidemias , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Masculino , Triglicerídeos , Doenças Cardiovasculares/complicações , Diabetes Mellitus/epidemiologia , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Fatores de Risco , Prognóstico , Acidente Vascular Cerebral/epidemiologia , Dislipidemias/diagnóstico , Dislipidemias/epidemiologia , Dislipidemias/complicações
13.
Toxicol Appl Pharmacol ; 456: 116279, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36243099

RESUMO

Sodium dichloroisocyanurate-96% (NaDCC) is commonly used to treat drinking water, industrial water, and wastewater. However, exposure to NaDCC by inhalation can have toxic pulmonary effects in humans. In the present study, we evaluated the potential toxicity of NaDCC following a 90-day inhalation toxicity study in Sprague-Dawley/Crl:CD (SD) rats. The animals were exposed to 0.4, 2.0, or 10.0 mg/m3 NaDCC for 90 days. In addition, male and female rats from the 10.0 mg/m3 group were set up as the recovery group for 14 days. The bronchoalveolar lavage fluid showed a concentration-dependent increase in the total cell count, with a significant increase in neutrophils in both the sexes in the 10.0 mg/m3 group compared to the negative control group. In the 10.0 mg/m3 group, lung organ weight was significantly increased among the female rats. Histopathological examination showed eosinophilic droplets in the olfactory/respiratory epithelium, mucous cell hyperplasia, atrophy/degeneration of the tracheal branches, and wall thickening of the alveolar ducts in the nasal cavity of both sexes in the 10.0 mg/m3 group. The adverse effects of NaDCC exposure were observed to decrease during the 14-day recovery period in both sexes. Based on pathological observations, the "no observed adverse effect concentration (NOAEC)" of inhaled NaDCC was 2.0 mg/m3 for both sexes. These results are expected to provide a scientific basis for inhalation toxicity data of NaDCC.


Assuntos
Exposição por Inalação , Pulmão , Humanos , Ratos , Animais , Masculino , Feminino , Ratos Sprague-Dawley , Administração por Inalação , Líquido da Lavagem Broncoalveolar , Exposição por Inalação/efeitos adversos
14.
Biotechnol Bioeng ; 119(11): 3252-3274, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35869574

RESUMO

Glioblastoma (GBM) is the most aggressive type of brain tumor that originates from glioblastoma stem cells (GSCs). In the brain, GSCs are supported by a tumor microenvironment (TME) residing in the perivascular niche and the hypoxic niche. The GBM TME is highly heterogenous and exhibits complex cell-to-cell interactions. Three-dimensional tumorspheres cultured in stem cell-enriching media is often used as an in vitro model. The GBM tumorspheres retain some of the transcriptional and translational GSC features but often fails to recapitulate intertumor heterogeneity. Here, we developed a simple, matrix-free, and in vivo-like GBM organoids (GBOs) using patient-derived xenograft GBM lines in small-scale bioreactors. Shear stress was optimized to produce highly reproducible GBOs over 1 mm diameter within 4-5 weeks. GBOs exhibited high stemness and strong cell-to-cell interactions compared to conventional tumorsphere cultures. They displayed spatial gradients of hypoxia-inducible factor 1α positive hypoxic cores where CD133-positive cells resided and spatially heterogeneous expression of NOTCH and its ligands. We also observed a self-established, hierarchically organized, and heterogeneous TME by GBM transdifferentiation into endothelial cells, pericytes, and astrocytes. Collectively, we demonstrate the ability to biomanufacture uniformly sized GBOs that recapitulate in vivo GBM TME features that can serve as an improved GBM in vitro model.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Transdiferenciação Celular , Células Endoteliais/metabolismo , Glioblastoma/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo , Organoides/metabolismo , Microambiente Tumoral
15.
Cells Tissues Organs ; 211(3): 282-293, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34077929

RESUMO

Most cancer deaths are caused by secondary metastasized tumors. The cells that spread these tumors are known as circulating tumor cells (CTCs). They exist in a dynamic environment, including exposure to fluid shear stress (FSS) that makes them susceptible to reactive oxygen species (ROS) generation. There are questions about the similarities of CTCs to cancer stem cells (CSCs) and whether the stem cell-like characteristics of CTCs allow them to proliferate and spread despite the biophysical obstacles during the metastatic process. One of those qualities is the ability to undergo the epithelial-to-mesenchymal transition (EMT). Here, MDA-MB-231 and MCF7 were modeled as CTCs by prolonged exposure to FSS using a spinner flask. They were tested for ROS generation, CSC, EMT, and Hippo pathway gene and protein markers using qRT-PCR and flow cytometry. MDA-MB-231 did not show significant changes in CSC markers, but did show significant changes in ROS, EMT, and Hippo markers (p < 0.05). Similarly, MCF7 showed significant changes in ROS and EMT markers (p < 0.05). Furthermore, both cell lines demonstrated the reverse mesenchymal-to-epithelial transition signature when allowed to recover after FSS. These results suggest that the degree of their stemness or aggressiveness affects their responses to externally applied biophysical forces and demonstrates a potential link between mechanotransduction, the Hippo pathway, and the induction of EMT in breast cancer cells.


Assuntos
Células Neoplásicas Circulantes , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Humanos , Mecanotransdução Celular , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
16.
Nicotine Tob Res ; 24(8): 1201-1207, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35323980

RESUMO

INTRODUCTION: Nicotine increases reinforcing effects of cigarette smoking by upregulating glutamate and dopamine releases via stimulation of nicotinic acetylcholine receptors (nAChRs) in the dorsal striatum (CPu). The present study was conducted to evaluate whether non-nicotine substances in cigarette smoke potentiate nicotine-induced behaviors by increasing glutamate and dopamine concentrations in the CPu. AIMS AND METHODS: Changes in the levels of glutamate and dopamine in the CPu were analyzed using a glutamate colorimetric assay and dopamine enzyme-linked immunosorbent assay, respectively, after repeated administration of nicotine or whole cigarette smoke condensate (WCSC) in male Sprague-Dawley rats. Changes in locomotion and drug-taking behavior were analyzed using the measurements of locomotor activity and self-administration under a fixed ratio 1 schedule in response to repeated administration of nicotine or WCSC. RESULTS: Repeated subcutaneous (s.c.) injections of nicotine (0.25 mg/kg/day) for 7 consecutive days significantly increased the levels of glutamate and dopamine in the CPu. Similar results were obtained from repeated injections of WCSC (0.25 mg/kg nicotine/day, s.c.) extracted from 3R4F Kentucky reference cigarettes. Parallel with the increases in the neurotransmitter levels in the CPu, both nicotine and WCSC increased locomotor activity and self-administration (0.03 mg/kg nicotine/infusion). However, repeated injections of WCSC did not change the nicotine-induced increases in neurotransmitter levels, locomotor activity, and self-administration. CONCLUSIONS: Nicotine rather than non-nicotine substances in WCSC play a major role in potentiating behavioral sensitization and drug-taking behavior via elevation of glutamate and dopamine concentrations in the CPu of rats. IMPLICATIONS: WCSC does not augment the nicotine-induced increases in behavioral sensitization, drug-taking behavior, and glutamate and dopamine concentrations, suggesting that non-nicotine substances do not potentiate the nicotine-induced behaviors by increasing the concentrations of the neurotransmitters in the CPu. These findings imply that nicotine, but not non-nicotine substances in WCSC, may be a major contributor that induces tobacco dependence in rats.


Assuntos
Dopamina , Nicotina , Animais , Glutamatos , Masculino , Nicotina/farmacologia , Ratos , Ratos Sprague-Dawley , Nicotiana
17.
Environ Res ; 204(Pt A): 111957, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34478728

RESUMO

To declare a shampoo toxicologically safe, one should evaluate the hazards posed by the inhalation of aerosols produced during its use. Herein, tap water was sprayed into a shampoo-filled plastic container to investigate the formation of shampoo aerosols and the possibility of their inhalation. The aerosols thus obtained had higher mass concentrations (geometric mean = 5779 µg m-3 (PM10) and 2249 µg m-3 (PM2.5)) than water aerosols (geometric mean = 927 µg m-3 (PM10) and 476 µg m-3 (PM2.5)). In particular, shampoo aerosol particles with an aerodynamic diameter of 2.5 µm, which can penetrate the alveoli when inhaled, had the highest mass concentration (geometric mean = 2000 µg m-3). The volatile organic compounds contained in shampoo aerosols featured alcohol and ether groups attached to dodecane and tetradecane backbones; these compounds were generated by the thermal decomposition of surfactants (i.e., lauryl and laureth sulfates) during instrumental analysis. The acquired data suggest that inhalation exposure and chronic inhalation toxicity evaluations should be performed for various shampoo usage conditions to ensure inhalation safety.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Exposição por Inalação , Tamanho da Partícula , Material Particulado/análise , Sulfatos
18.
Environ Res ; 209: 112866, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35134376

RESUMO

In this study, the composition of mainstream smoke was investigated with an emphasis on a list of volatile organic compounds (VOCs: e.g., isoprene, acrylonitrile, methyl ethyl ketone, benzene, toluene, m-xylene and styrene) using the two types of flavor capsule cigarettes (FCCs, here coded as F1 and F2) in reference to one commercial, non-flavored (NF) and 3R4F cigarette. The concentrations of all the target compounds from FCCs were quantified under two contrasting conditions (i.e., with and without breaking the capsules). The effect of breaking the capsule was apparent in the FCC products with the enhancement of VOC levels, specifically between after and before breaking the capsules (e.g., 1.10-1.58 folds (benzene) and 1.30-1.53 folds (acetonitrile)). Such increases were apparent in both FCC samples if assessed in terms of the total amount of VOCs (TVOC): (1) F1 (from 2159 to 2530 µg cig-1 (p = 9.42 × 10-6)) and (2) F2 (from 1470 to 2014 µg cig-1 (p = 0.05)). In addition, these TVOC levels determined from the FCCs were 1.62- to 1.83- and 1.29- to 1.46-fold higher than those of the NF cigarette and the 3R4F cigarette, respectively. Thus, these FCC products are suspected to play a role as stronger sources of VOCs than the general cigarette products.


Assuntos
Produtos do Tabaco , Compostos Orgânicos Voláteis , Benzeno/análise , Fumaça , Nicotiana , Compostos Orgânicos Voláteis/análise
19.
Sensors (Basel) ; 22(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35746159

RESUMO

It is necessary to convert to automation in a tomato hydroponic greenhouse because of the aging of farmers, the reduction in agricultural workers as a proportion of the population, COVID-19, and so on. In particular, agricultural robots are attractive as one of the ways for automation conversion in a hydroponic greenhouse. However, to develop agricultural robots, crop monitoring techniques will be necessary. In this study, therefore, we aimed to develop a maturity classification model for tomatoes using both support vector classifier (SVC) and snapshot-type hyperspectral imaging (VIS: 460-600 nm (16 bands) and Red-NIR: 600-860 nm (15 bands)). The spectral data, a total of 258 tomatoes harvested in January and February 2022, was obtained from the tomatoes' surfaces. Spectral data that has a relationship with the maturity stages of tomatoes was selected by correlation analysis. In addition, the four different spectral data were prepared, such as VIS data (16 bands), Red-NIR data (15 bands), combination data of VIS and Red-NIR (31 bands), and selected spectral data (6 bands). These data were trained by SVC, respectively, and we evaluated the performance of trained classification models. As a result, the SVC based on VIS data achieved a classification accuracy of 79% and an F1-score of 88% to classify the tomato maturity into six stages (Green, Breaker, Turning, Pink, Light-red, and Red). In addition, the developed model was tested in a hydroponic greenhouse and was able to classify the maturity stages with a classification accuracy of 75% and an F1-score of 86%.


Assuntos
COVID-19 , Solanum lycopersicum , Humanos , Imagens, Psicoterapia
20.
Inorg Chem ; 60(4): 2138-2148, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33534562

RESUMO

Ruthenium complexes bearing protic diimine ligands are cytotoxic to certain cancer cells upon irradiation with blue light. Previously reported complexes of the type [(N,N)2Ru(6,6'-dhbp)]Cl2 with 6,6'-dhbp = 6,6'-dihydroxybipyridine and N,N = 2,2'-bipyridine (bipy) (1A), 1,10-phenanthroline (phen) (2A), and 2,3-dihydro-[1,4]dioxino[2,3-f][1,10]phenanthroline (dop) (3A) show EC50 values as low as 4 µM (for 3A) vs breast cancer cells upon blue light irradiation ( Inorg. Chem. 2017, 56, 7519). Herein, subscript A denotes the acidic form of the complex bearing OH groups, and B denotes the basic form bearing O- groups. This photocytotoxicity was originally attributed to photodissociation, but recent results suggest that singlet oxygen formation is a more plausible cause of photocytotoxicity. In particular, bulky methoxy substituents enhance photodissociation but these complexes are nontoxic ( Dalton Trans 2018, 47, 15685). Cellular studies are presented herein that show the formation of reactive oxygen species (ROS) and apoptosis indicators upon treatment of cells with complex 3A and blue light. Singlet oxygen sensor green (SOSG) shows the formation of 1O2 in cell culture for cells treated with 3A and blue light. At physiological pH, complexes 1A-3A are deprotonated to form 1B-3B in situ. Quantum yields for 1O2 (ϕΔ) are 0.87 and 0.48 for 2B and 3B, respectively, and these are an order of magnitude higher than the quantum yields for 2A and 3A. The values for Ï•Δ show an increase with 6,6'-dhbp derived substituents as follows: OMe < OH < O-. TD-DFT studies show that the presence of a low lying triplet metal-centered (3MC) state favors photodissociation and disfavors 1O2 formation for 2A and 3A (OH groups). However, upon deprotonation (O- groups), the 3MLCT state is accessible and can readily lead to 1O2 formation, but the dissociative 3MC state is energetically inaccessible. The changes to the energy of the 3MLCT state upon deprotonation have been confirmed by steady state luminescence experiments on 1A-3A and their basic analogs, 1B-3B. This energy landscape favors 1O2 formation for 2B and 3B and leads to enhanced toxicity for these complexes under physiological conditions. The ability to convert readily from OH to O- groups allowed us to investigate an electronic change that is not accompanied by steric changes in this fundamental study.


Assuntos
Antineoplásicos/química , Complexos de Coordenação/química , Luz , Processos Fotoquímicos , Compostos de Rutênio/química , Oxigênio Singlete/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Hipóxia Celular , Linhagem Celular Tumoral , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Prótons , Oxigênio Singlete/metabolismo , Espectrofotometria Ultravioleta
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