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1.
Nature ; 620(7972): 181-191, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37380767

RESUMO

The adult human breast is comprised of an intricate network of epithelial ducts and lobules that are embedded in connective and adipose tissue1-3. Although most previous studies have focused on the breast epithelial system4-6, many of the non-epithelial cell types remain understudied. Here we constructed the comprehensive Human Breast Cell Atlas (HBCA) at single-cell and spatial resolution. Our single-cell transcriptomics study profiled 714,331 cells from 126 women, and 117,346 nuclei from 20 women, identifying 12 major cell types and 58 biological cell states. These data reveal abundant perivascular, endothelial and immune cell populations, and highly diverse luminal epithelial cell states. Spatial mapping using four different technologies revealed an unexpectedly rich ecosystem of tissue-resident immune cells, as well as distinct molecular differences between ductal and lobular regions. Collectively, these data provide a reference of the adult normal breast tissue for studying mammary biology and diseases such as breast cancer.


Assuntos
Mama , Perfilação da Expressão Gênica , Análise de Célula Única , Adulto , Feminino , Humanos , Mama/citologia , Mama/imunologia , Mama/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Células Endoteliais/classificação , Células Endoteliais/metabolismo , Células Epiteliais/classificação , Células Epiteliais/metabolismo , Genômica , Imunidade
2.
J Immunol ; 210(11): 1677-1686, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37083696

RESUMO

Transplantation of human neural stem cells (hNSCs) is a promising regenerative therapy to promote remyelination in patients with multiple sclerosis (MS). Transplantation of hNSCs has been shown to increase the number of CD4+CD25+Foxp3+ T regulatory cells (Tregs) in the spinal cords of murine models of MS, which is correlated with a strong localized remyelination response. However, the mechanisms by which hNSC transplantation leads to an increase in Tregs in the CNS remains unclear. We report that hNSCs drive the conversion of T conventional (Tconv) cells into Tregs in vitro. Conversion of Tconv cells is Ag driven and fails to occur in the absence of TCR stimulation by cognate antigenic self-peptides. Furthermore, CNS Ags are sufficient to drive this conversion in the absence of hNSCs in vitro and in vivo. Importantly, only Ags presented in the thymus during T cell selection drive this Treg response. In this study, we investigate the mechanisms by which hNSC Ags drive the conversion of Tconv cells into Tregs and may provide key insight needed for the development of MS therapies.


Assuntos
Esclerose Múltipla , Células-Tronco Neurais , Humanos , Camundongos , Animais , Linfócitos T Reguladores , Linfócitos T CD4-Positivos , Esclerose Múltipla/terapia , Ativação Linfocitária , Fatores de Transcrição Forkhead , Antígenos CD4
3.
J Am Chem Soc ; 146(7): 4830-4841, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38346096

RESUMO

A thorough comprehension of the mechanism underlying the methanol oxidation reaction (MOR) on Ni-based catalysts is critical for future electrocatalytic design and development. However, the mechanism of MOR on these materials remains a matter of controversy. Herein, we combine in situ surface-enhanced infrared absorption spectroscopy (SEIRAS) and density functional theory (DFT) calculations to identify the active sites and determine the mechanism of MOR on monometallic Ni-based catalysts in alkaline media. The SEIRAS results show that formate and (bi)carbonate are formed after the commencement of the MOR with potential-dependent relative distributions. These spectroscopic results are in good agreement with the DFT-computed reaction profiles over an oxygen vacancy, suggesting that the MOR mainly proceeds through the formate-involving pathway, in which the early consumption of methanol yields formate as the major product, while increasing potential drives further oxidation of formate to (bi)carbonate. We also find a parallel pathway for the generation of (bi)carbonate at high potentials that bypasses the formation of formate. The two main pathways are thermodynamically more feasible than the one predominantly reported in the literature for MOR on NiOOH that involves CHO and/or CO as key intermediates. These DFT results are supported by spectroscopic evidence showing that no band associated with CHO or CO can be detected by SEIRAS, which is attributed to the nature of the oxygen vacancies as the active sites, suppressing deep dehydrogenation of CH2O to CHO. This work thus shows the promising role of defect engineering in promoting the electrocatalytic MOR activity and selectivity.

4.
J Neurochem ; 168(2): 69-82, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38178803

RESUMO

N-acetylaspartate (NAA) is an abundant central nervous system amino acid derivative that is tightly coupled to mitochondria and energy metabolism in neurons. A reduced NAA signature is a prominent early pathological biomarker in multiple neurodegenerative diseases and becomes progressively more pronounced as disease advances. Because NAA synthesis requires aspartate drawn directly from mitochondria, we argued that this process is in direct competition with oxidative phosphorylation for substrate and that sustained high levels of NAA synthesis would be incompatible with pathological energy crisis. We show here that over-expression of the rate-limiting NAA synthetic enzyme in the hippocampus of the 5x familial Alzheimer's disease (5xFAD) mouse results in an exaggerated pathological ATP deficit and accelerated cognitive decline. Over-expression of NAA synthase did not increase amyloid burden or result in cell loss but did significantly deplete mitochondrial aspartate and impair the ability of mitochondria to oxidize glutamate for adenosine triphosphate (ATP) synthesis. These results define NAA as a sink for energetic substrate and suggest initial pathological reductions in NAA are part of a response to energetic crisis designed to preserve substrate bioavailability for mitochondrial ATP synthesis.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Ácido Aspártico/metabolismo , Trifosfato de Adenosina/metabolismo
5.
Emerg Infect Dis ; 30(1): 136-140, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38147063

RESUMO

We assessed tuberculosis (TB) diagnostic delays among patients with TB and COVID-19 in California, USA. Among 58 persons, 43% experienced TB diagnostic delays, and a high proportion (83%) required hospitalization for TB. Even when viral respiratory pathogens circulate widely, timely TB diagnostic workup for at-risk persons remains critical for reducing TB-related illness.


Assuntos
COVID-19 , Tuberculose , Humanos , Diagnóstico Tardio , COVID-19/diagnóstico , California/epidemiologia , Resultado do Tratamento , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Teste para COVID-19
6.
Chem Pharm Bull (Tokyo) ; 72(1): 61-67, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38220213

RESUMO

Two novel series of quinazolinone-based hybrids, including quinazolinone-1,3,4-oxadiazoles (10a-l) and quinazolinone-1,3,4-oxadiazole-benzimidazoles (8a-e), were designed and synthesized and their cytotoxic activities against three human cancer cell lines, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MCF-7), were evaluated. The cytotoxic assays revealed that 10i with a lipophilic 4-fluoro-phenyl moiety at the C-2 position of the quinazolinone ring displayed good cytotoxicities against the A549 and MCF-7 cell lines, while 8b-d with the thioether-linked benzimidazole moiety incorporated on the right side of the oxadiazole ring induced comparable stronger activities toward the MCF-7 cell line, relative to the simple two-heterocycle-containing hybrid 10i. These novel quinazolinone-based hybrids could be considered as lead compounds that merit further optimization and development as anti-cancer agents.


Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Relação Estrutura-Atividade , Células MCF-7 , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Linhagem Celular Tumoral , Estrutura Molecular
7.
Molecules ; 27(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408604

RESUMO

Epigenetic alterations found in all human cancers are promising targets for anticancer therapy. In this sense, histone deacetylase inhibitors (HDACIs) are interesting anticancer agents that play an important role in the epigenetic regulation of cancer cells. Here, we report 15 novel hydroxamic acid-based histone deacetylase inhibitors with quinazolinone core structures. Five compounds exhibited antiproliferative activity with IC50 values of 3.4-37.8 µM. Compound 8 with a 2-mercaptoquinazolinone cap moiety displayed the highest antiproliferative efficacy against MCF-7 cells. For the HDAC6 target selectivity study, compound 8 displayed an IC50 value of 2.3 µM, which is 29.3 times higher than those of HDAC3, HDAC4, HDAC8, and HDAC11. Western blot assay proved that compound 8 strongly inhibited tubulin acetylation, a substrate of HDAC6. Compound 8 also displayed stronger inhibition activity against HDAC11 than the control drug Belinostat. The inhibitory mechanism of action of compound 8 on HDAC enzymes was then explored using molecular docking study. The data revealed a high binding affinity (-7.92 kcal/mol) of compound 8 toward HDAC6. In addition, dock pose analysis also proved that compound 8 might serve as a potent inhibitor of HDAC11.


Assuntos
Antineoplásicos , Inibidores de Histona Desacetilases , Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Epigênese Genética , Desacetilase 6 de Histona , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Proteínas Repressoras/metabolismo , Relação Estrutura-Atividade
8.
Dev Dyn ; 249(5): 646-655, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31872525

RESUMO

BACKGROUND: Dysfunction of GABAergic and glutamatergic neurons in the brain, which establish inhibitory and excitatory networks, respectively, may cause diverse neurological disorders. The mechanism underlying the determination of GABAergic vs. glutamatergic neurotransmitter phenotype in the caudal diencephalon remains largely unknown. RESULTS: In this study, we investigated the consequence of Tcf7l2 (transcription factor 7-like 2) ablation on the neurotransmitter identity of GABAergic and glutamatergic neurons in the caudal diencephalon. We identified positive and negative activity in the control of glutamatergic and GABAergic neuronal gene expression by Tcf7l2. Loss of Tcf7l2 did not alter the initial acquisition of the neurotransmitter identity in thalamic neurons. However, glutamatergic thalamic neurons failed to maintain their excitatory neurotransmitter phenotype in the absence of Tcf7l2. Moreover, a subset of Tcf7l2-deficient thalamic neurons underwent a glutamatergic to GABAergic neurotransmitter identity switch. Our data indicate that Tcf7l2 may promote glutamatergic neuronal differentiation and repress GABAergic neurotransmitter identity in the caudal thalamus. CONCLUSIONS: This study provides evidence for a novel and crucial role of Tcf7l2 in the molecular mechanism by which the neurotransmitter identity of glutamatergic thalamic neurons is established. Our findings exemplify a clear case of neurotransmitter identity regulation that is partitioned into initiation and maintenance phases.


Assuntos
Tálamo , Proteína 2 Semelhante ao Fator 7 de Transcrição , Diencéfalo , Neurônios/metabolismo , Neurotransmissores/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo
9.
Adv Exp Med Biol ; 1292: 37-63, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30838542

RESUMO

BACKGROUND: The sequence polymorphism of mitochondrial DNA (mtDNA) hypervariable segment 1 (HV1) and hypervariable segment 2 (HV2) is studied and applied to genetic diversity and human evolution assessment, forensic genetics, consanguinity determination, and mitochondrial disease diagnosis. METHODS: The study identified the variations of HV1 and HV2 of 517 unrelated Vietnamese individuals in Kinh, Muong, Cham, and Khmer ethnic. We performed sequencing of two hypervariable segments of mitochondrial DNA: HV1 and HV2. RESULTS: Fifty haplogroups were identified in which F1a haplogroup frequency was highest at 15.7%, followed by B5a (10.8%), M (8.9%), and M7b1 (7.7%). The most frequently encountered SNPs in this study were A263G (100%), A73G (99.6%), 315insC (96%), 309insC (56%), C16223T (41%), and T16189C (39%). The genetic diversity was calculated at 99.83%, and the probability of random match of two individuals sharing the same mtDNA haplotype was 0.37%. CONCLUSION: We have assessed the genetic polymorphism of mtDNA HV1 and HV2 of 517 Kinh, Muong, Cham, and Khmer ethnic samples. The result will help in better understanding of Vietnamese's mitochondrial genome diversity and aid in population as well as forensic science.


Assuntos
Povo Asiático/genética , DNA Mitocondrial/genética , Etnicidade/genética , Polimorfismo Genético , Haplótipos , Humanos , Análise de Sequência de DNA , Vietnã
10.
Lab Invest ; 97(7): 843-853, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28581486

RESUMO

The Hippo signaling pathway and the Notch signaling pathway are evolutionary conserved signaling cascades that have important roles in embryonic development of many organs. In murine liver, disruption of either pathway impairs intrahepatic bile duct development. Recent studies suggested that the Notch signaling receptor Notch2 is a direct transcriptional target of the Hippo signaling pathway effector YAP, and the Notch signaling is a major mediator of the Hippo signaling in maintaining biliary cell characteristics in adult mice. However, it remains to be determined whether the Hippo signaling pathway functions through the Notch signaling in intrahepatic bile duct development. We found that loss of the Hippo signaling pathway tumor suppressor Nf2 resulted in increased expression levels of the Notch signaling pathway receptor Notch2 in cholangiocytes but not in hepatocytes. When knocking down Notch2 on the background of Nf2 deficiency in mouse livers, the excessive bile duct development induced by Nf2 deficiency was suppressed by heterozygous and homozygous deletion of Notch2 in a dose-dependent manner. These results implicated that Notch signaling is one of the downstream effectors of the Hippo signaling pathway in regulating intrahepatic bile duct development.


Assuntos
Ductos Biliares Intra-Hepáticos/crescimento & desenvolvimento , Neurofibromatose 2/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptor Notch2/metabolismo , Animais , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Feminino , Via de Sinalização Hippo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurofibromatose 2/genética , Proteínas Serina-Treonina Quinases/genética , Receptor Notch2/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-27562181

RESUMO

BACKGROUND: The evaluation of the QT interval in the presence of left bundle branch block (LBBB) is associated with the challenge to discriminate native QT interval from the prolongation due to the increase in QRS duration. The newest formula to evaluate QT interval in the presence of LBBB suggests: modified QT during LBBB = measured QT interval minus 50% of LBBB duration. The purpose of this study is therefore to validate the abovementioned formula in the clinical setting. METHODS: Validation in two separate groups of patients: Patients who alternated between narrow QRS and intermittent LBBB and patients with narrow QRS who developed LBBB after transcatheter aortic valve implantation (TAVI). RESULTS: The acquired mean native QTc intervals and those calculated by the presented formula displayed no significant differences (p > .99 and p > .75). CONCLUSIONS: In this study we proved for the first time the validity and applicability of the experimentally acquired formula for the evaluation of the QT interval in the presence of LBBB in a clinical setting.


Assuntos
Bloqueio de Ramo/fisiopatologia , Eletrocardiografia/métodos , Fascículo Atrioventricular/fisiopatologia , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
12.
Yale J Biol Med ; 88(2): 145-55, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26029013

RESUMO

Targeting synthetic lethal interactions is a promising new therapeutic approach to exploit specific changes that occur within cancer cells. Multiple approaches to investigate these interactions have been developed and successfully implemented, including chemical, siRNA, shRNA, and CRISPR library screens. Genome-wide computational approaches, such as DAISY, also have been successful in predicting synthetic lethal interactions from both cancer cell lines and patient samples. Each approach has its advantages and disadvantages that need to be considered depending on the cancer type and its molecular alterations. This review discusses these approaches and examines case studies that highlight their use.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Terapia Genética/métodos , Terapia de Alvo Molecular/métodos , Neoplasias/fisiopatologia , Neoplasias/terapia , Animais , Descoberta de Drogas , Humanos , Neoplasias/patologia
13.
Lab Invest ; 94(12): 1406-18, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25365204

RESUMO

Cholangiopathies are characterized by dysregulation of the balance between biliary growth and loss. We have shown that histamine (HA) stimulates biliary growth via autocrine mechanisms. To evaluate the paracrine effects of mast cell (MC) stabilization on biliary proliferation, sham or BDL rats were treated by IP-implanted osmotic pumps filled with saline or cromolyn sodium (24 mg/kg BW/day (inhibits MC histamine release)) for 1 week. Serum, liver blocks and cholangiocytes were collected. Histidine decarboxylase (HDC) expression was measured using real-time PCR in cholangiocytes. Intrahepatic bile duct mass (IBDM) was evaluated by IHC for CK-19. MC number was determined using toluidine blue staining and correlated to IBDM. Proliferation was evaluated by PCNA expression in liver sections and purified cholangiocytes. We assessed apoptosis using real-time PCR and IHC for BAX. Expression of MC stem factor receptor, c-kit, and the proteases chymase and tryptase were measured by real-time PCR. HA levels were measured in serum by EIA. In vitro, MCs and cholangiocytes were treated with 0.1% BSA (basal) or cromolyn (25 µM) for up to 48 h prior to assessing HDC expression, HA levels and chymase and tryptase expression. Supernatants from MCs treated with or without cromolyn were added to cholangiocytes before measuring (i) proliferation by MTT assays, (ii) HDC gene expression by real-time PCR and (iii) HA release by EIA. In vivo, cromolyn treatment decreased BDL-induced: (i) IBDM, MC number, and biliary proliferation; (ii) HDC and MC marker expression; and (iii) HA levels. Cromolyn treatment increased cholangiocyte apoptosis. In vitro, cromolyn decreased HA release and chymase and tryptase expression in MCs but not in cholangiocytes. Cromolyn-treated MC supernatants decreased biliary proliferation and HA release. These studies provide evidence that MC histamine is key to biliary proliferation and may be a therapeutic target for the treatment of cholangiopathies.


Assuntos
Ductos Biliares Intra-Hepáticos/patologia , Colestase/tratamento farmacológico , Cromolina Sódica/farmacologia , Liberação de Histamina/efeitos dos fármacos , Mastócitos/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Ratos , Ratos Endogâmicos F344
14.
Am J Physiol Gastrointest Liver Physiol ; 307(8): G813-23, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25169977

RESUMO

Histidine is converted to histamine by histidine decarboxylase (HDC). We have shown that cholangiocytes 1) express HDC, 2) secrete histamine, and 3) proliferate after histamine treatment via ERK1/2 signaling. In bile duct-ligated (BDL) rodents, there is enhanced biliary hyperplasia, HDC expression, and histamine secretion. This studied aimed to demonstrate that knockdown of HDC inhibits biliary proliferation via downregulation of PKA/ERK1/2 signaling. HDC(-/-) mice and matching wild-type (WT) were subjected to sham or BDL. After 1 wk, serum, liver blocks, and cholangiocytes were collected. Immunohistochemistry was performed for 1) hematoxylin and eosin, 2) intrahepatic bile duct mass (IBDM) by cytokeratin-19, and 3) HDC biliary expression. We measured serum and cholangiocyte histamine levels by enzyme immunoassay. In total liver or cholangiocytes, we studied: 1) HDC and VEGF/HIF-1α expression and 2) PCNA and PKA/ERK1/2 protein expression. In vitro, cholangiocytes were stably transfected with shRNA-HDC plasmids (or control). After transfection we evaluated pPKA, pERK1/2, and cholangiocyte proliferation by immunoblots and MTT assay. In BDL HDC(-/-) mice, there was decreased IBDM, PCNA, VEGF, and HDC expression compared with BDL WT mice. Histamine levels were decreased in BDL HDC(-/-). BDL HDC(-/-) livers were void of necrosis and inflammation compared with BDL WT. PKA/ERK1/2 protein expression (increased in WT BDL) was lower in BDL HDC(-/-) cholangiocytes. In vitro, knockdown of HDC decreased proliferation and protein expression of PKA/ERK1/2 compared with control. In conclusion, loss of HDC decreases BDL-induced biliary mass and VEGF/HIF-1α expression via PKA/ERK1/2 signaling. Our data suggest that HDC is a key regulator of biliary proliferation.


Assuntos
Ductos Biliares/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Histidina Descarboxilase/metabolismo , Sistema de Sinalização das MAP Quinases , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Ductos Biliares/enzimologia , Ductos Biliares/patologia , Proliferação de Células , Regulação para Baixo , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Deleção de Genes , Histamina/sangue , Histamina/metabolismo , Histidina Descarboxilase/genética , Hiperplasia/enzimologia , Hiperplasia/metabolismo , Fígado/metabolismo , Camundongos
15.
BMC Public Health ; 14: 556, 2014 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-24898950

RESUMO

BACKGROUND: Introduction of human papillomavirus (HPV) vaccine in national programs has proceeded apace since 2006, mostly in high-income countries. Recently concluded pilots of HPV vaccination in low-income countries have provided important lessons learned for these settings; however, rigorous evaluations of the feasibility of these delivery strategies that effectively reach young adolescents have been few. This paper presents results from a qualitative evaluation of a demonstration program which implemented school-based and health center-based HPV vaccinations to all girls in grade 6, or 11 years of age, for two years in four districts of Vietnam. METHODS: Using semi-structured interviews of 131 health and education staff from local, district, province, and national levels and 26 focus-group discussions with local project implementers (n = 153), we conducted a qualitative two-year evaluation to measure the impact of HPV vaccinations on the health and education systems. RESULTS: HPV vaccine delivery at schools or health centers was made feasible by: a. close collaboration between the health and education sectors, b. detailed planning for implementation, c. clearly defined roles and responsibilities for project implementers, d. effective management and supervision of vaccinations during delivery, and e. engagement with community organizations for support. Both the health and education systems were temporarily challenged with the extra workload, but the disruptions were short-lived (a few days for each of three doses) and perceived as worth the longer-term benefit of cervical cancer prevention. CONCLUSION: The learning from Vietnam has identified critical elements for successful vaccine delivery that can provide a model for other countries to consider during their planning of national rollout of HPV vaccine.


Assuntos
Programas de Imunização/organização & administração , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Serviços de Saúde Escolar , Atitude do Pessoal de Saúde , Criança , Atenção à Saúde , Docentes , Estudos de Viabilidade , Feminino , Grupos Focais , Programas Governamentais , Humanos , Gravidez , Pesquisa Qualitativa , Vietnã
16.
Heliyon ; 10(10): e31118, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38770332

RESUMO

Electromagnetic interference (EMI) shielding material is the most effective solution to protect electronic devices and human health from the harmful effects of electromagnetic radiation. The study of EMI shielding materials is intensifying in the constantly developing picture of the fourth industrial revolution. Many EMI shielding materials based on metal, carbon, emerging MXene materials, and their composites have been discovered to utilize the EMI shielding performance. However, a huge demand for compact and multi-functional devices requires the integration of new functions into EMI shielding materials. Multifunctional EMI shielding materials perform multiple functions beyond their main function of EMI shielding in a system due to their specific properties. The additional functions can either naturally exist or be specially engineered. This review summarizes the recent progress of cutting-edge multifunctional EMI shielding materials. The possibility of combining multifunction EMI shielding materials, such as strain sensing, humidity sensing, temperature sensing, thermal management, etc., and the difficulties in balancing EMI shielding performance with other functions are also discussed. Lastly, we point out challenges and propose future directions to develop research on multifunctional EMI shielding materials.

17.
Front Cell Dev Biol ; 12: 1336308, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344749

RESUMO

The mechanism underlying the differentiation of the dorsal midbrain into two morphologically and functionally distinct compartments, the inferior colliculus (IC) and superior colliculus (SC), which process auditory and visual information, respectively, remains largely unexplored. By using null and conditional alleles, we uncover the roles of a homeodomain transcription factor Dbx1 in the regulation of IC and SC differentiation. We show that Dbx1 regulates GABAergic neuron development in the dorsal midbrain. In the absence of Dbx1 function, the dorsal-most m1-m2 progenitor domains in the midbrain fail to activate GABAergic neuron-specific gene expression and instead switch to a glutamatergic phenotype. These results identify Dbx1 as a dorsal midbrain-specific GABAergic determinant that regulates the selector genes, Helt, Gata2, and Tal2. Furthermore, we demonstrate that maturation of the dorsal midbrain into the IC and SC is dependent on Dbx1. Null mutation of Dbx1 impairs the identity and fate of IC and SC neurons. Surprisingly, Dbx1 is required for preventing IC into SC fate switch and thus Dbx1-deficient IC neurons undergo acquisition of SC identity. Conditional inactivation of Dbx1 at late developmental phase leads to alteration in the identity and fate of the IC, but not the SC. These results suggest that SC differentiation is dependent on the early function of Dbx1, and that the IC requires the prolonged action for its normal formation. Furthermore, we uncover that Tcf7l2 acts downstream of Dbx1 selectively to promote IC differentiation. Altogether, our study identifies a molecular mechanism underlying spatial and temporal control of dorsal midbrain development.

18.
Med Acupunct ; 36(1): 12-20, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38380169

RESUMO

Objective: Primary dysmenorrhea is a common condition that impacts quality of life significantly. Auricular therapies have shown promise for treating primary dysmenorrhea, but there is a lack of evidence specifically for auricular acupuncture (AA). This study evaluated the safety and efficacy of AA for managing primary dysmenorrhea. Materials and Methods: A randomized, double-blinded controlled trial was conducted on 90 females with primary dysmenorrhea: an AA group; n = 45) and a sham-AA (SA) group; n = 45. Specific ear acupoints (i.e., Uterus, Endocrine, Shenmen, Subcortex, Liver, and Kidney) were used for the intervention, which was 1 or 2 days prior to the expected menstruation onset. Outcomes were visual analogue scale (VAS) scores, ibuprofen needs, and adverse events (AEs). Results: The AA group had significantly lower VAS scores, compared to the SA group at menstruation onset and for up to 12 hours (mean differences [MDs] and 95% confidence intervals [CIs]: -1.08 [-1.96, -0.21] and -1.17 [-2.16, -0.18], respectively). Both groups had reductions in pain levels, compared to the prior menstrual cycle; the AA group had a significantly greater improvement. The AA group needed fewer ibuprofen tablets (MD: -0.28; 95% CI: -0.58, 0.00]). AEs were mild pain and irritation at insertion sites, all resolved spontaneously with no lasting effects. Conclusions: AA is safe. It may be effective for managing primary dysmenorrhea. Further studies are warranted on AA's effectiveness in diverse populations and extended times.

19.
ACS Appl Opt Mater ; 2(5): 704-713, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38808252

RESUMO

Water-soluble dipyridinium thiazolo[5,4-d]thiazole (TTz) compounds are incorporated into inexpensive poly(vinyl alcohol) (PVA)/borax films and exhibit fast (<1 s), high-contrast photochromism, photofluorochromism, and oxygen sensing. Under illumination, the films change from clear/yellow TTz2+ to purple TTz•+ and then blue TTz0. The contrast and speed of the photochromism are dependent on the polymer matrix redox properties and the concentration of TTz2+. The photoreduced films exhibit strong, near-infrared light (1000-1500 nm) absorbances in addition to visible color changes. Spectroscopic ellipsometry was used to establish the complex dielectric function for the TTz2+ and TTz0 states. Incorporating non-photochromic dyes yields yellow-to-green and pink-to-purple photochromism. Additionally, when illuminated, reversible photoactuation occurs, causing mechanical contraction in the TTz-embedded films. The blue film returns to its colorless state via exposure to O2, making the films able to sense oxygen and leak direction for smart packaging. These films show potential for use in self-tinting smart windows, eyeglasses, displays, erasable memory devices, fiber optic communication, and oxygen sensing.

20.
bioRxiv ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39211101

RESUMO

Vulvar diseases are a critical yet often neglected area of women's health, profoundly affecting patients' quality of life and frequently resulting in long-term physical and psychological challenges. Lichen sclerosus (LS) is a chronic inflammatory skin disorder that predominantly affects the vulva, leading to severe itching, pain, scarring, and an increased risk of malignancy. Despite its profound impact on affected individuals, the molecular pathogenesis of vulvar LS (VLS) is not well understood, hindering the development of FDA-approved therapies. Here, we utilize single-cell and spatial transcriptomics to analyze lesional and non-lesional skin from VLS patients, as well as healthy control vulvar skin. Our findings demonstrate histologic, cellular, and molecular heterogeneities within VLS, yet highlight unifying molecular changes across keratinocytes, fibroblasts, immune cells, and melanocytes in lesional skin. They reveal cellular stress and damage in fibroblasts and keratinocytes, enhanced T cell activation and cytotoxicity, aberrant cell-cell signaling, and increased activation of the IFN, JAK/STAT, and p53 pathways in specific cell types. Using both monolayer and organotypic culture models, we also demonstrate that knockdown of select genes, which are downregulated in VLS lesional keratinocytes, partially recapitulates VLS-like stress-associated changes. Collectively, these data provide novel insights into the pathogenesis of VLS, identifying potential biomarkers and therapeutic targets for future research.

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