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1.
J Vis Exp ; (209)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39072632

RESUMO

The preterm neonatal airway epithelium is constantly exposed to environmental stressors. One of these stressors in neonates with lung disease includes oxygen (O2) tension higher than the ambient atmosphere - termed hyperoxia (>21% O2). The effect of hyperoxia on the airway depends on various factors, including the developmental stage of the airway, the degree of hyperoxia, and the duration of exposure, with variable exposures potentially leading to unique phenotypes. While there has been extensive research on the effect of hyperoxia on neonatal lung alveolarization and airway hyperreactivity, little is known about the short and long-term underlying effect of hyperoxia on human neonatal airway epithelial cells. A major reason for this is the scarcity of an effective in vitro model to study human neonatal airway epithelial development and function. Here, we describe a method for isolating and expanding human neonatal tracheal airway epithelial cells (nTAECs) utilizing human neonatal tracheal aspirates and culturing these cells in air-liquid interface (ALI) culture. We demonstrate that nTAECs form a mature polarized cell-monolayer in ALI culture and undergo mucociliary differentiation. We also present a method for moderate hyperoxia exposure of the cell monolayer in ALI culture using a specialized incubator. Additionally, we describe an assay to measure cellular oxidative stress following hyperoxia exposure in ALI culture using fluorescent quantification, which confirms that moderate hyperoxia exposure induces cellular oxidative stress but does not cause significant cell membrane damage or apoptosis. This model can potentially be used to simulate clinically relevant hyperoxia exposure encountered by neonatal airways in the Neonatal Intensive Care Unit (NICU) and used to study the short and long-lasting effects of O2 on neonatal airway epithelial programming. Studies using this model could be utilized to explore ways to mitigate early-life oxidative injury to developing airways, which is implicated in the development of long-term airway diseases in former premature infants.


Assuntos
Células Epiteliais , Hiperóxia , Humanos , Recém-Nascido , Hiperóxia/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/citologia , Traqueia/citologia , Traqueia/metabolismo , Técnicas de Cultura de Células em Três Dimensões/métodos , Mucosa Respiratória/citologia , Mucosa Respiratória/metabolismo , Técnicas de Cultura de Células/métodos
2.
Chem Res Toxicol ; 37(7): 1155-1170, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38924487

RESUMO

In 2012, the U.S. Food & Drug Administration (FDA) published an established list of 93 harmful and potentially harmful constituents (HPHCs) targeting four tobacco product types (cigarettes, cigarette tobacco, roll-your-own tobacco, smokeless tobacco). In 2016, the FDA finalized the deeming rule to regulate electronic nicotine delivery systems (ENDS). However, knowledge gaps exist regarding whether certain HPHCs are present in ENDS e-liquids and aerosols. We identified and addressed these gaps by conducting literature searches and then experimentally quantifying HPHCs in the e-liquid and aerosol of 37 ENDS brands based on gaps in the literature. The literature searches identified 66 e-liquid HPHCs and 68 aerosol HPHCs that have limited to no information regarding the quantifiability of these constituents. A contracted ISO 17025 accredited laboratory performed the HPHC quantifications. The availability of validated analytical methods in the contracted laboratory determined the HPHCs included in the study scope (63/66 for e-liquids, 64/68 for aerosols). Combining the results from the quantifications and literature searches, 36 (39%) and 34 (37%) HPHCs were found quantifiable (≥limit of quantification [LOQ]) in ENDS e-liquids and aerosols, respectively, with 25 HPHCs being quantifiable in both matrices. Quantifiability results imply potential HPHC transfers between matrices, leaching from components, or formations from aerosol generation. The study results can inform the scientific basis for manufacturers and regulators regarding regulatory requirements for HPHC reporting. The HPHC quantities can also inform evaluations of the public health impact of ENDS and public communications regarding ENDS health risks.


Assuntos
Aerossóis , Sistemas Eletrônicos de Liberação de Nicotina , Aerossóis/análise , Aerossóis/química , Humanos , Nicotina/análise
3.
Sci Rep ; 14(1): 10308, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705881

RESUMO

Knowledge of near-bottom ocean current velocities and especially their extreme values is necessary to understand geomorphology of the seafloor and composition of benthic biological communities and quantify mechanical energy dissipation by bottom drag. Direct measurements of near-bottom currents in deep ocean remain scarce because of logistical challenges. Here, we report the results of flow velocity and pressure fluctuation measurements at three sites with depths of 2573-4443 m in the area where the Gulf Stream interacts with the New England Seamounts. Repeated episodes of unexpectedly strong near-bottom currents were observed, with the current speed at 4443 m of more than 0.40 m/s. At 2573 m, current speeds exceeded 0.20 m/s approximately 5% of the time throughout the entire eight-week measurement period. The maximum flow speeds of over 1.10 m/s recorded at this site significantly surpass the fastest previously reported directly measured current speeds at comparable or larger depths. A strong correlation is found between the noise intensity in the infrasonic band and the measured current speed. The noise intensity and the characteristic frequency increase with the increasing current speed. Machine-learning tools are employed to infer current speeds from flow-noise measurements at the site not equipped with a current meter.

4.
Mol Cancer Ther ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38797955

RESUMO

AB598 is a CD39 inhibitory antibody being pursued for the treatment of solid tumors in combination with chemotherapy and immunotherapy. CD39 metabolizes extracellular ATP (eATP), an alarmin capable of promoting anti-tumor immune responses, into adenosine, an immuno-inhibitory metabolite. By inhibiting CD39, the consumption of eATP is reduced, resulting in a pro-inflammatory milieu in which eATP can activate myeloid cells to promote anti-tumor immunity. The preclinical characterization of AB598 provides a mechanistic rationale for combining AB598 with chemotherapy in the clinic. Chemotherapy can induce ATP release from tumor cells and, when preserved by AB598, both chemotherapy-induced eATP and exogenously added ATP promote the function of monocyte-derived dendritic cells via P2Y11 signaling. Inhibition of CD39 in the presence of ATP can promote inflammasome activation in in vitro-derived macrophages, an effect mediated by P2X7. In a MOLP8 murine xenograft model, AB598 results in full inhibition of intratumoral enzymatic activity, an increase in intratumoral ATP, a decrease of extracellular CD39 on tumor cells, and ultimately, control of tumor growth. In cynomolgus monkeys, systemically dosed AB598 results in effective enzymatic inhibition in tissues, full peripheral and tissue target engagement, and a reduction in cell surface CD39 both in tissues and in the periphery. Taken together, these data support a promising therapeutic strategy of harnessing the eATP generated by standard-of-care chemotherapies to prime the tumor microenvironment for a productive anti-tumor immune response.

5.
Cancer Res ; 84(12): 1978-1995, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38635895

RESUMO

T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is an inhibitory receptor on immune cells that outcompetes an activating receptor, CD226, for shared ligands. Tumor-infiltrating lymphocytes express TIGIT and CD226 on regulatory T cells (Treg) and on CD8+ T cells with tumor-reactive or exhausted phenotypes, supporting the potential of therapeutically targeting TIGIT to enhance antitumor immunity. To optimize the efficacy of therapeutic antibodies against TIGIT, it is necessary to understand IgG Fc (Fcγ) receptor binding for therapeutic benefit. In this study, we showed that combining Fc-enabled (Fce) or Fc-silent (Fcs) anti-TIGIT with antiprogrammed cell death protein 1 in mice resulted in enhanced control of tumors by differential mechanisms: Fce anti-TIGIT promoted the depletion of intratumoral Treg, whereas Fcs anti-TIGIT did not. Despite leaving Treg numbers intact, Fcs anti-TIGIT potentiated the activation of tumor-specific exhausted CD8+ populations in a lymph node-dependent manner. Fce anti-TIGIT induced antibody-dependent cell-mediated cytotoxicity against human Treg in vitro, and significant decreases in Treg were measured in the peripheral blood of patients with phase I solid tumor cancer treated with Fce anti-TIGIT. In contrast, Fcs anti-TIGIT did not deplete human Treg in vitro and was associated with anecdotal objective clinical responses in two patients with phase I solid tumor cancer whose peripheral Treg frequencies remained stable on treatment. Collectively, these data provide evidence for pharmacologic activity and antitumor efficacy of anti-TIGIT antibodies lacking the ability to engage Fcγ receptor. SIGNIFICANCE: Fcs-silent anti-TIGIT antibodies enhance the activation of tumor-specific pre-exhausted T cells and promote antitumor efficacy without depleting T regulatory cells.


Assuntos
Receptores Imunológicos , Linfócitos T Reguladores , Animais , Linfócitos T Reguladores/imunologia , Camundongos , Receptores Imunológicos/imunologia , Receptores Imunológicos/antagonistas & inibidores , Humanos , Linfócitos do Interstício Tumoral/imunologia , Feminino , Linfócitos T CD8-Positivos/imunologia , Camundongos Endogâmicos C57BL , Linhagem Celular Tumoral , Neoplasias/imunologia , Neoplasias/tratamento farmacológico
6.
Circ Res ; 134(10): 1330-1347, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557119

RESUMO

BACKGROUND: Tetraspanin CD151 is highly expressed in endothelia and reinforces cell adhesion, but its role in vascular inflammation remains largely unknown. METHODS: In vitro molecular and cellular biological analyses on genetically modified endothelial cells, in vivo vascular biological analyses on genetically engineered mouse models, and in silico systems biology and bioinformatics analyses on CD151-related events. RESULTS: Endothelial ablation of Cd151 leads to pulmonary and cardiac inflammation, severe sepsis, and perilous COVID-19, and endothelial CD151 becomes downregulated in inflammation. Mechanistically, CD151 restrains endothelial release of proinflammatory molecules for less leukocyte infiltration. At the subcellular level, CD151 determines the integrity of multivesicular bodies/lysosomes and confines the production of exosomes that carry cytokines such as ANGPT2 (angiopoietin-2) and proteases such as cathepsin-D. At the molecular level, CD151 docks VCP (valosin-containing protein)/p97, which controls protein quality via mediating deubiquitination for proteolytic degradation, onto endolysosomes to facilitate VCP/p97 function. At the endolysosome membrane, CD151 links VCP/p97 to (1) IFITM3 (interferon-induced transmembrane protein 3), which regulates multivesicular body functions, to restrain IFITM3-mediated exosomal sorting, and (2) V-ATPase, which dictates endolysosome pH, to support functional assembly of V-ATPase. CONCLUSIONS: Distinct from its canonical function in strengthening cell adhesion at cell surface, CD151 maintains endolysosome function by sustaining VCP/p97-mediated protein unfolding and turnover. By supporting protein quality control and protein degradation, CD151 prevents proteins from (1) buildup in endolysosomes and (2) discharge through exosomes, to limit vascular inflammation. Also, our study conceptualizes that balance between degradation and discharge of proteins in endothelial cells determines vascular information. Thus, the IFITM3/V-ATPase-tetraspanin-VCP/p97 complexes on endolysosome, as a protein quality control and inflammation-inhibitory machinery, could be beneficial for therapeutic intervention against vascular inflammation.


Assuntos
COVID-19 , Endossomos , Lisossomos , Tetraspanina 24 , Animais , Lisossomos/metabolismo , Tetraspanina 24/metabolismo , Tetraspanina 24/genética , Humanos , Camundongos , COVID-19/metabolismo , COVID-19/imunologia , COVID-19/patologia , Endossomos/metabolismo , Camundongos Knockout , Vasculite/metabolismo , Camundongos Endogâmicos C57BL , SARS-CoV-2 , Inflamação/metabolismo , Inflamação/patologia , Sepse/metabolismo
7.
J Hum Hypertens ; 38(4): 307-313, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438602

RESUMO

Blood Pressure Variability (BPV) is associated with cardiovascular risk and serum uric acid level. We investigated whether BPV was lowered by allopurinol and whether it was related to neuroimaging markers of cerebral small vessel disease (CSVD) and cognition. We used data from a randomised, double-blind, placebo-controlled trial of two years allopurinol treatment after recent ischemic stroke or transient ischemic attack. Visit-to-visit BPV was assessed using brachial blood pressure (BP) recordings. Short-term BPV was assessed using ambulatory BP monitoring (ABPM) performed at 4 weeks and 2 years. Brain MRI was performed at baseline and 2 years. BPV measures were compared between the allopurinol and placebo groups, and with CSVD and cognition. 409 participants (205 allopurinol; 204 placebo) were included in the visit-to-visit BPV analyses. There were no significant differences found between placebo and allopurinol groups for any measure of visit-to-visit BPV. 196 participants were included in analyses of short-term BPV at week 4. Two measures were reduced by allopurinol: the standard deviation (SD) of systolic BP (by 1.30 mmHg (95% confidence interval (CI) 0.18-2.42, p = 0.023)); and the average real variability (ARV) of systolic BP (by 1.31 mmHg (95% CI 0.31-2.32, p = 0.011)). There were no differences in other measures at week 4 or in any measure at 2 years, and BPV was not associated with CSVD or cognition. Allopurinol treatment did not affect visit-to-visit BPV in people with recent ischemic stroke or TIA. Two BPV measures were reduced at week 4 by allopurinol but not at 2 years.


Assuntos
Hipertensão , Ataque Isquêmico Transitório , AVC Isquêmico , Humanos , Pressão Sanguínea , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/etiologia , Alopurinol/uso terapêutico , AVC Isquêmico/complicações , AVC Isquêmico/tratamento farmacológico , Ácido Úrico , Fatores de Risco , Monitorização Ambulatorial da Pressão Arterial
8.
PLOS Digit Health ; 3(2): e0000403, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38306391

RESUMO

Low-middle income countries like India bear a heavier burden of maternal, childcare, and child mortality rates when compared with high-income countries, which highlights the disparity in global health. Numerous societal, geopolitical, economic, and institutional issues have been linked to this inequality. mHealth has the potential to ameliorate these challenges by providing health services and health-related information with the assistance of frontline workers in the provision of prepartum, delivery, and postnatal care to improve maternal and child health outcomes in hard-to-reach areas in low- and middle-income countries (LMICs). However, there is limited evidence to support how mHealth can strengthen maternal and child health in India. The scoping review guideline in the Cochrane Handbook was used to retrieve studies from 4 international databases: CINAHL, Embase, Medline Ovid, and PubMed. This search strategy used combined keywords (MeSH terms) related to maternal and child healthcare, mHealth, and BIMARU in conjunction with database-controlled vocabulary. Out of 278 records, 8 publications were included in the review. The included articles used mHealth for data collection, eLearning, communication, patient monitoring, or tracking to deliver maternal and neonatal care. The results of these papers reflected a favourable effect of mHealth on the target population and found that it altered their attitudes and behaviours about healthcare. Higher job satisfaction and self-efficiency were reported by mHealth user care providers. Multiple barriers to the acceptance of mHealth exist, but the majority of the evidence points towards the feasibility of the intervention in a clinical setting. The mHealth has positive potential for improving maternal and child health outcomes in low-resource settings in India's BIMARU states by strengthening the healthcare system. The results of the study could be used in the tailoring of an effective mHealth intervention and implementation strategy in a similar context. However, there is a need for economic evaluation in the future to bridge the knowledge gap regarding the cost-effectiveness of mHealth interventions.

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