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1.
Cell ; 184(25): 6101-6118.e13, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34852236

RESUMEN

CD4 T follicular helper (TFH) cells support B cells, which are critical for germinal center (GC) formation, but the importance of TFH-B cell interactions in cancer is unclear. We found enrichment of TFH cell transcriptional signature correlates with GC B cell signature and with prolonged survival in individuals with lung adenocarcinoma (LUAD). We further developed a murine LUAD model in which tumor cells express B cell- and T cell-recognized neoantigens. Interactions between tumor-specific TFH and GC B cells, as well as interleukin (IL)-21 primarily produced by TFH cells, are necessary for tumor control and effector CD8 T cell function. Development of TFH cells requires B cells and B cell-recognized neoantigens. Thus, tumor neoantigens can regulate the fate of tumor-specific CD4 T cells by facilitating their interactions with tumor-specific B cells, which in turn promote anti-tumor immunity by enhancing CD8 T cell effector functions.


Asunto(s)
Adenocarcinoma/inmunología , Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Interleucinas/inmunología , Neoplasias Pulmonares/inmunología , Animales , Linfocitos B/citología , Linfocitos T CD4-Positivos/citología , Linfocitos T CD8-positivos/citología , Línea Celular Tumoral , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
2.
Immunity ; 55(3): 475-493.e5, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35216666

RESUMEN

CD4+ T cell-derived interleukin 21 (IL-21) sustains CD8+ T cell responses during chronic viral infection, but the helper subset that confers this protection remains unclear. Here, we applied scRNA and ATAC-seq approaches to determine the heterogeneity of IL-21+CD4+ T cells during LCMV clone 13 infection. CD4+ T cells were comprised of three transcriptionally and epigenetically distinct populations: Cxcr6+ Th1 cells, Cxcr5+ Tfh cells, and a previously unrecognized Slamf6+ memory-like (Tml) subset. T cell differentiation was specifically redirected toward the Tml subset during chronic, but not acute, LCMV infection. Although this subset displayed an enhanced capacity to accumulate and some developmental plasticity, it remained largely quiescent, which may hinder its helper potential. Conversely, mixed bone marrow chimera experiments revealed that Tfh cell-derived IL-21 was critical to sustain CD8+ T cell responses and viral control. Thus, strategies that bolster IL-21+Tfh cell responses may prove effective in enhancing CD8+ T cell-mediated immunity.


Asunto(s)
Células T Auxiliares Foliculares , Virosis , Linfocitos T CD8-positivos , Humanos , Interleucinas
3.
Nature ; 622(7983): 514-520, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37731002

RESUMEN

The highly energy-intensive iron and steel industry contributed about 25% (ref. 1) of global industrial CO2 emissions in 2019 and is therefore critical for climate-change mitigation. Despite discussions of decarbonization potentials at national and global levels2-6, plant-specific mitigation potentials and technologically driven pathways remain unclear, which cumulatively determines the progress of net-zero transition of the global iron and steel sector. Here we develop a CO2 emissions inventory of 4,883 individual iron and steel plants along with their technical characteristics, including processing routes and operating details (status, age, operation-years etc.). We identify and match appropriate emission-removal or zero-emission technologies to specific possessing routes, or what we define thereafter as a techno-specific decarbonization road map for every plant. We find that 57% of global plants have 8-24 operational years, which is the retrofitting window for low-carbon technologies. Low-carbon retrofitting following the operational characteristics of plants is key for limiting warming to 2 °C, whereas advanced retrofitting may help limit warming to 1.5 °C. If each plant were retrofitted 5 years earlier than the planned retrofitting schedule, this could lead to cumulative global emissions reductions of 69.6 (±52%) gigatonnes (Gt) CO2 from 2020 to 2050, almost double that of global CO2 emissions in 2021. Our results provide a detailed picture of CO2 emission patterns associated with production processing of iron and steel plants, illustrating the decarbonization pathway to the net-zero-emissions target with the efforts from each plant.

4.
Nature ; 619(7968): 151-159, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37344588

RESUMEN

The peripheral T cell repertoire of healthy individuals contains self-reactive T cells1,2. Checkpoint receptors such as PD-1 are thought to enable the induction of peripheral tolerance by deletion or anergy of self-reactive CD8 T cells3-10. However, this model is challenged by the high frequency of immune-related adverse events in patients with cancer who have been treated with checkpoint inhibitors11. Here we developed a mouse model in which skin-specific expression of T cell antigens in the epidermis caused local infiltration of antigen-specific CD8 T cells with an effector gene-expression profile. In this setting, PD-1 enabled the maintenance of skin tolerance by preventing tissue-infiltrating antigen-specific effector CD8 T cells from (1) acquiring a fully functional, pathogenic differentiation state, (2) secreting significant amounts of effector molecules, and (3) gaining access to epidermal antigen-expressing cells. In the absence of PD-1, epidermal antigen-expressing cells were eliminated by antigen-specific CD8 T cells, resulting in local pathology. Transcriptomic analysis of skin biopsies from two patients with cutaneous lichenoid immune-related adverse events showed the presence of clonally expanded effector CD8 T cells in both lesional and non-lesional skin. Thus, our data support a model of peripheral T cell tolerance in which PD-1 allows antigen-specific effector CD8 T cells to co-exist with antigen-expressing cells in tissues without immunopathology.


Asunto(s)
Antígenos , Linfocitos T CD8-positivos , Tolerancia Inmunológica , Receptor de Muerte Celular Programada 1 , Piel , Animales , Humanos , Ratones , Antígenos/inmunología , Biopsia , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Epidermis/inmunología , Epidermis/metabolismo , Perfilación de la Expresión Génica , Liquen Plano/inmunología , Liquen Plano/patología , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Piel/citología , Piel/inmunología , Piel/metabolismo , Piel/patología
5.
Semin Immunol ; 69: 101797, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37343412

RESUMEN

With the emergence and success of checkpoint blockade immunotherapy, immuno-oncology has primarily focused on CD8 T cells, whose cytotoxic programs directly target tumor cells. However, the limited response rate of current immunotherapy regimens has prompted investigation into other types of tumor-infiltrating immune cells, such as CD4 T cells and B cells, and how they interact with CD8 T cells in a coordinated network. Recent studies have demonstrated the potential therapeutic benefits of CD4 T follicular helper (TFH) cells and B cells in cancer, highlighting the important role of their crosstalk and interactions with other immune cell components in the tumor microenvironment. These interactions also occur in tumor-associated tertiary lymphoid structures (TLS), which resemble secondary lymphoid organs (SLOs) with orchestrated vascular, chemokine, and cellular infrastructures that support the developmental pathways of functional immune cells. In this review, we discuss recent breakthroughs on TFH biology and T cell-B cell interactions in tumor immunology, and their potential as novel therapeutic targets to advance cancer treatment.


Asunto(s)
Neoplasias , Estructuras Linfoides Terciarias , Humanos , Células T Auxiliares Foliculares/metabolismo , Células T Auxiliares Foliculares/patología , Linfocitos B , Linfocitos T CD8-positivos , Microambiente Tumoral
6.
Brain ; 147(6): 2128-2143, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38226680

RESUMEN

Alzheimer's disease is neurodegenerative and characterized by progressive cognitive impairment. Synaptic dysfunction appears in the early stage of Alzheimer's disease and is significantly correlated with cognitive impairment. However, the specific regulatory mechanism remains unclear. Here, we found the transcription factor Maf1 to be upregulated in Alzheimer's disease and determined that conditional knockout of Maf1 in a transgenic mouse model of Alzheimer's disease restored learning and memory function; the downregulation of Maf1 reduced the intraneuronal calcium concentration and restored neuronal synaptic morphology. We also demonstrated that Maf1 regulated the expression of NMDAR1 by binding to the promoter region of Grin1, further regulating calcium homeostasis and synaptic remodelling in neurons. Our results clarify the important role and mechanism of the Maf1-NMDAR1 signalling pathway in stabilizing synaptic structure, neuronal function and behaviour during Alzheimer's disease pathogenesis. This therefore serves as a potential diagnostic and therapeutic target for the early stage of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Ratones Transgénicos , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Disfunción Cognitiva/genética , Disfunción Cognitiva/metabolismo , Espinas Dendríticas/metabolismo , Espinas Dendríticas/patología , Modelos Animales de Enfermedad , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Proteínas Represoras/genética , Proteínas Represoras/metabolismo
7.
Small ; 20(14): e2306666, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37990400

RESUMEN

Carrier-selective passivating contacts using transition metal oxides (TMOs) have attracted great attention for crystalline silicon (c-Si) heterojunction solar cells recently. Among them, tantalum oxide (Ta2O5) exhibits outstanding advantages, such as a wide bandgap, good surface passivation, and a small conduction band offset with c-Si, which is typically used as an electron-selective contact layer. Interestingly, it is first demonstrated that solution-processed Ta2O5 films exhibit a high hole selectivity, which blocks electrons and promotes hole transport simultaneously. Through the ozone pre-treatment of Ta2O5/p-Si interface and optimization of the film thickness (≈9 nm), the interfacial recombination is suppressed and the contact resistivity is reduced from 178.0 to 29.3 mΩ cm2. Moreover, the Sn4+ doping increases both the work function and oxygen vacancies of the film, contributing to the improved hole-selective contact performance. As a result, the photoelectric conversion efficiencies of Ta2O5/p-Si heterojunction solar cells are significantly improved from 14.84% to 18.47%, with a high thermal stability up to 300 °C. The work has provided a feasible strategy to explore new features of TMOs for carrier-selective contact applications, that is, bipolar carrier transport properties.

8.
Mol Biol Rep ; 51(1): 258, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302635

RESUMEN

Breast cancer (BC) is one of the most common malignant tumors in women and still poses a significant threat to women worldwide. Recurrence of BC in situ, metastasis to distant organs, and resistance to chemotherapy are all attached to high mortality in patients with BC. Non-coding RNA (ncRNA) of the type known as "circRNA" links together from one end to another to create a covalently closed, single-stranded circular molecule. With characteristics including plurality, evolutionary conservation, stability, and particularity, they are extensively prevalent in various species and a range of human cells. CircRNAs are new and significant contributors to several kinds of disorders, including cardiovascular disease, multiple organ inflammatory responses and malignancies. Recent studies have shown that circRNAs play crucial roles in the occurrence of breast cancer by interacting with miRNAs to regulate gene expression at the transcriptional or post-transcriptional levels. CircRNAs offer the potential to be therapeutic targets for breast cancer treatment as well as prospective biomarkers for early diagnosis and prognosis of BC. Here, we are about to present an overview of the functions of circRNAs in the proliferation, invasion, migration, and resistance to medicines of breast cancer cells and serve as a promising resource for future investigations on the pathogenesis and therapeutic strategies.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Humanos , Femenino , ARN Circular/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , MicroARNs/genética , Biomarcadores
9.
Immun Ageing ; 21(1): 55, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103919

RESUMEN

Sarcopenia is a complex age-associated syndrome of progressive loss of muscle mass and strength. Although this condition is influenced by many factors, age-related changes in immune function including immune cell dynamics, and chronic inflammation contribute to its progression. The complex interplay between the immune system, gut-muscle axis, and autophagy further underscores their important roles in sarcopenia pathogenesis. Immunomodulation has emerged as a promising strategy to counteract sarcopenia. Traditional management approaches to treat sarcopenia including physical exercise and nutritional supplementation, and the emerging technologies of biophysical stimulation demonstrated the importance of immunomodulation and regulation of macrophages and T cells and reduction of chronic inflammation. Treatments to alleviate low-grade inflammation in older adults by modulating gut microbial composition and diversity further combat sarcopenia. Furthermore, some pharmacological interventions, nano-medicine, and cell therapies targeting muscle, gut microbiota, or autophagy present additional avenues for immunomodulation in sarcopenia. This narrative review explores the immunological underpinnings of sarcopenia, elucidating the relationship between the immune system and muscle during ageing. Additionally, the review discusses new areas such as the gut-muscle axis and autophagy, which bridge immune system function and muscle health. Insights into current and potential approaches for sarcopenia management through modulation of the immune system are provided, along with suggestions for future research directions and therapeutic strategies. We aim to guide further investigation into clinical immunological biomarkers and identify indicators for sarcopenia diagnosis and potential treatment targets to combat this condition. We also aim to draw attention to the importance of considering immunomodulation in the clinical management of sarcopenia.

10.
Subcell Biochem ; 103: 95-120, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37120466

RESUMEN

Musculoskeletal ageing is a major health challenge as muscles and bones constitute around 55-60% of body weight. Ageing muscles will result in sarcopenia that is characterized by progressive and generalized loss of skeletal muscle mass and strength with a risk of adverse outcomes. In recent years, a few consensus panels provide new definitions for sarcopenia. It was officially recognized as a disease in 2016 with an ICD-10-CM disease code, M62.84, in the International Classification of Diseases (ICD). With the new definitions, there are many studies emerging to investigate the pathogenesis of sarcopenia, exploring new interventions to treat sarcopenia and evaluating the efficacy of combination treatments for sarcopenia. The scope of this chapter is to summarize and appraise the evidence in terms of (1) clinical signs, symptoms, screening, and diagnosis, (2) pathogenesis of sarcopenia with emphasis on mitochondrial dysfunction, intramuscular fat infiltration and neuromuscular junction deterioration, and (3) current treatments with regard to physical exercises and nutritional supplement.


Asunto(s)
Sarcopenia , Humanos , Sarcopenia/diagnóstico , Sarcopenia/terapia , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Envejecimiento/fisiología , Ejercicio Físico
11.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34620712

RESUMEN

Wolbachia bacteria, inherited through the female germ line, infect a large fraction of arthropod species. Many Wolbachia strains manipulate host reproduction, most commonly through cytoplasmic incompatibility (CI). CI, a conditional male sterility, results when Wolbachia-infected male insects mate with uninfected females; viability is restored if the female is similarly infected (called "rescue"). CI is used to help control mosquito-borne viruses such as dengue and Zika, but its mechanisms remain unknown. The coexpressed CI factors CifA and CifB form stable complexes in vitro, but the timing and function of this interaction in the insect are unresolved. CifA expression in the female germ line is sufficient for rescue. We report high-resolution structures of a CI-factor complex, CinA-CinB, which utilizes a unique binding mode between the CinA rescue factor and the CinB nuclease; the structures were validated by biochemical and yeast growth analyses. Importantly, transgenic expression in Drosophila of a nonbinding CinA mutant, designed based on the CinA-CinB structure, suggests CinA expressed in females must bind CinB imported by sperm in order to rescue embryonic viability. Binding between cognate factors is conserved in an enzymatically distinct CI system, CidA-CidB, suggesting universal features in Wolbachia CI induction and rescue.


Asunto(s)
Drosophila melanogaster/microbiología , Embrión no Mamífero/embriología , Infertilidad Masculina/fisiopatología , Reproducción/fisiología , Wolbachia/metabolismo , Animales , Animales Modificados Genéticamente , Drosophila melanogaster/genética , Desarrollo Embrionario , Femenino , Masculino , Control de Mosquitos/métodos , Complejos Multiproteicos/metabolismo , Unión Proteica , Simbiosis , Enfermedades Transmitidas por Vectores/prevención & control , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/virología
12.
BMC Surg ; 24(1): 164, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38797851

RESUMEN

PURPOSE: As a minimally invasive procedure, laser hemorrhoidoplasty (LHP) can not only relieve the symptoms of hemorrhoids, but also protect the anal cushion structure. This study aimed to investigate the clinical efficacy of LHP in the treatment of grade II hemorrhoids. METHODS: A total of 70 patients with grade II hemorrhoids were randomly assigned to receive LHP or Rubber Band Ligation (RBL) (n = 35 per group) in 2019 from a single center. The postoperative pain, bleeding, feeling of anal distension(local falling, swelling, foreign body sensation, stool) and postoperative recurrence rate were compared between the two groups. RESULTS: The postoperative pain, bleeding, and feeling of anal distension in the LHP group were improved significantly as compared with the RBL group within 2 weeks after surgery (P < 0.01). Both methods can relieve the symptoms of grade II hemorrhoids. There was no difference in the recurrence rate between the two groups at 1 year after surgery (P > 0.05). The patients in LHP group took less time to return to normal activities (P < 0.001). CONCLUSIONS: As a minimally invasive treatment, LHP is easy and not traumatic and results in mild postoperative pain and few complications. It is an ideal choice for grade II hemorrhoids.


Asunto(s)
Hemorreoidectomía , Hemorroides , Terapia por Láser , Humanos , Hemorroides/cirugía , Masculino , Ligadura/métodos , Femenino , Persona de Mediana Edad , Hemorreoidectomía/métodos , Adulto , Terapia por Láser/métodos , Resultado del Tratamiento , Dolor Postoperatorio/etiología , Dolor Postoperatorio/diagnóstico , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Recurrencia
13.
Surgeon ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39129087

RESUMEN

BACKGROUND: Surgical site infection (SSI) remains a critical postoperative complication after total hip and knee arthroplasty (THA and TKA). Frailty, a condition characterized by decreased physiological reserve and increased vulnerability to stressors, may influence the risk of SSI in these patients. This meta-analysis aims to evaluate the association between frailty and the incidence of SSI following THA or TKA. METHODS: A systematic search of databases including PubMed, EMBASE, Web of Science, Wanfang, and CNKI was conducted to identify relevant studies. Data were extracted and pooled using a random-effects model to calculate the overall risk ratio (RR) and 95 % confidence intervals (CIs). RESULTS: A total of ten studies comprising 1,036,787 patients met the inclusion criteria. The meta-analysis revealed that frail patients undergoing THA or TKA had a significantly higher risk of developing SSI compared to non-frail patients (RR = 1.64, 95 % CI: 1.39-1.93, p < 0.001, I2 = 66 %). Subgroup analyses indicated that the type of arthroplasty (hip vs. knee) and the method of frailty assessment did not significantly alter the association. Further subgroup analysis suggested that frailty was significantly associated with a higher incidence of deep SSI including joint infection (RR = 1.77, 95 % CI: 1.27-1.48, p < 0.001), but not the incidence of superficial SSI (RR = 1.57, 95 % CI: 0.45-5.42, p = 0.48). The association between frailty and SSI remains in subgroup of multivariate studies only (RR = 1.56, 95 % CI: 1.34 to 1.80, p < 0.001). CONCLUSIONS: Frailty is a potential predictor of SSI following TKA/THA.

14.
J Occup Environ Hyg ; 21(5): 319-325, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38416473

RESUMEN

N95 respirators are the core equipment used by healthcare workers to prevent the spread of respiratory diseases. The protective effect of N95 against infection spread depends on the fit of the N95 to the wearer, which is related to the wearer's facial dimensions. The purpose of this cross-sectional study was to assess the relationship between the fit of three types of N95 and facial dimensions. A total of 305 healthcare workers from ten hospitals in Beijing were recruited for this study. Facial dimensions of workers were measured using Intel RealSense Depth Camera D435. Fit testing was conducted on three types of N95 using the TSI-8038 Porta Count Pro + Respirator Fit Tester. Possible associations between the fit test results and facial dimension data were examined. A Porta Count reading of 100 was used as the criterion for an acceptable fit. The fit of the folding respirators was positively correlated with nose length (r = 0.13, p = 0.02), nose height (r = 0.14, p = 0.02), and face width (r = 0.12, p = 0.03), whereas that of flat respirators was correlated with nose width (r = 0.16, p < 0.01), chin length (r = 0.18, p < 0.01), and pro-face width (r = 0.13, p = 0.02), and that of arched respirators was correlated with the nose length (r = 0.13, p = 0.03). The fit of N95 for wearers depends on their facial features. The results of this study can provide advice for medical workers to choose the appropriate N95. Medical staff should fully consider their facial dimensions when choosing an appropriate N95 to improve the protective efficacy of respirators and to reduce the risk of infection by respiratory diseases.


Asunto(s)
Cara , Respiradores N95 , Humanos , Cara/anatomía & histología , Adulto , Masculino , Estudios Transversales , Femenino , Persona de Mediana Edad , Personal de Salud , Diseño de Equipo , Beijing , Dispositivos de Protección Respiratoria/normas , Exposición Profesional/prevención & control
15.
Opt Express ; 31(4): 5699-5707, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36823843

RESUMEN

Stimulated Brillouin scattering (SBS) is a non-linear process which has the capacity to improve the beam quality and pulse characteristics of laser beams. In this paper, we theoretically and experimentally study the process of SBS in fused silica. In particular, we examine the energy reflection and pulse compression of input laser pulses as functions of focus position, pump energy and beam diameter. We utilized coupled wave equations and a distributed noise model to simulate the reflected energy and time waveform under different gain parameters. An experimental system is constructed and used to qualify the numerical simulations. The results reveal that the threshold for the SBS process and the energy reflectivity significantly change with laser focus position under the same pump and focusing parameters. Ultimately, the gain characteristics of the SBS material is the primary factor that influences the SBS output. This work presented here offers insight into the operation of short-length solid-state SBS lasers and serves as a basis for the design and optimization of such systems.

16.
Opt Express ; 31(19): 30030-30039, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37710555

RESUMEN

Analyzing the longitudinal-mode of a pump can significantly prevent optical damage to solid media and expand the applications of solid media in high repetition rate stimulated Brillouin scattering (SBS). In this study, a Fabry-Pérot etalon was used to control the number of longitudinal-mode in a pump laser output. We studied the output characteristics of SBS in fused silica by considering both single- and multi-longitudinal-mode pumping. We analyzed and compared variations in the SBS threshold, energy reflectivity, linewidth, and waveform characteristics. The experimental results indicated that a pump operating in a single-longitudinal-mode had a 14% lower SBS threshold than one operating in a multi-longitudinal-mode. The proportion of the weak longitudinal-mode in the multi-longitudinal-mode was close to the threshold difference. The damage threshold of the multi-longitudinal-mode pumps was approximately 35 mJ (@12 ns, f = 300 mm). The Stokes linewidth and waveform exhibited opposite trends as the energy changed. Due to the time-bandwidth product, the linewidth and waveform tended to converge towards the pump. This study emphasizes the importance of using a single-longitudinal-mode pump in the development and use of solid-state SBS gain media.

17.
Artículo en Inglés | MEDLINE | ID: mdl-37486319

RESUMEN

Currently, there are four mainstream taxonomic opinions on the classification of the class Halobacteria at the family and order levels. The International Committee on Systematics of Prokaryotes Subcommittee on the Taxonomy of Halobacteria (ICSP), List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Centre for Biotechnology Information (NCBI) adopted taxonomies have three to four orders and up to eight families, while the Genome Taxonomy Database (GTDB) taxonomy proposes only one order with nine families. To resolve the taxonomic inconsistency, phylogenomic analyses based on concatenated single-copy orthologous proteins and 122 concatenated conserved single-copy marker proteins were conducted to infer the taxonomic status of the current representatives of the class Halobacteria at the family and order levels. The current 76 genera with validly published names of the class Halobacteria were able to be assigned into eight families in one order. On the basis of these results, it is proposed that the current species with validly published names of the class Halobacteria should be remerged into the order Halobacteriales, then assigned to eight families, Haladaptataceae, Haloarculaceae, Halobacteriaceae, Halococcaceae, Haloferacaceae, Natronoarchaeaceae, Natrialbaceae and Halorubellaceae. Thus, Haladaptataceae fam. nov. is described based on Haladaptatus, Halomicrococcus and Halorussus and Halorubellaceae fam. nov. is proposed incorporating Haloarchaeobius and Halorubellus, respectively.


Asunto(s)
Ácidos Grasos , Halobacteriales , Humanos , Análisis de Secuencia de ADN , Filogenia , ARN Ribosómico 16S/genética , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química
18.
Nanotechnology ; 34(30)2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37094553

RESUMEN

SnO2film is one of the most widely used electron transport layers (ETL) in perovskite solar cells (PSCs). However, the inherent surface defect states in SnO2film and mismatch of the energy level alignment with perovskite limit the photovoltaic performance of PSCs. It is of great interesting to modify SnO2ETL with additive, aiming to decrease the surface defect states and obtain well aligned energy level with perovskite. In this paper, anhydrous copper chloride (CuCl2) was employed to modify the SnO2ETL. It is found that the adding of a small amount of CuCl2into the SnO2ETL can improve the proportion of Sn4+in SnO2, passivate oxygen vacancies at the surface of SnO2nanocrystals, improve the hydrophobicity and conductivity of ETL, and obtain a good energy level alignment with perovskite. As a result, both the photoelectric conversion efficiency (PCE) and stability of the PSCs based on SnO2ETLs modified with CuCl2(SnO2-CuCl2) is improved in comparison with that of the PSCs on pristine SnO2ETLs. The optimal PSC based on SnO2-CuCl2ETL exhibits a much higher PCE of 20.31% as compared to the control device (18.15%). The unencapsulated PSCs with CuCl2modification maintain 89.3% of their initial PCE after exposing for 16 d under ambient conditions with a relative humidity of 35%. Cu(NO3)2was also employed to modify the SnO2ETL and achieved a similar effect as that of CuCl2, indicating that the cation Cu2+plays the main role in SnO2ETL modification.

19.
Cardiovasc Drugs Ther ; 37(3): 571-584, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35796905

RESUMEN

Cardiovascular diseases (CVDs) are the leading cause of death globally. Atherosclerosis is the basis of major CVDs - myocardial ischemia, heart failure, and stroke. Among numerous functional molecules, the transcription factor nuclear factor κB (NF-κB) has been linked to downstream target genes involved in atherosclerosis. The activation of the NF-κB family and its downstream target genes in response to environmental and cellular stress, hypoxia, and ischemia initiate different pathological events such as innate and adaptive immunity, and cell survival, differentiation, and proliferation. Thus, NF-κB is a potential therapeutic target in the treatment of atherosclerosis and related CVDs. Several biologics and small molecules as well as peptide/proteins have been shown to regulate NF-κB dependent signaling pathways. In this review, we will focus on the function of NF-κB in CVDs and the role of NF-κB inhibitors in the treatment of CVDs.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Insuficiencia Cardíaca , Humanos , FN-kappa B/metabolismo , Transducción de Señal/fisiología
20.
Phys Chem Chem Phys ; 25(47): 32364-32371, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37990808

RESUMEN

To explore the dynamics of metal-to-ligand charge transfer (MLCT) excited states involving covalently bonded dimetal units, a series of quadruply bonded dimolybdenum (Mo2) complexes, namely, [Mo2]-ph, [Mo2]-naph, and [Mo2]-anth, were synthesized and characterized. Our investigations reveal a non-radiative process associated with the deactivation of the MLCT state into a low-lying dimetal-centered triplet state (3Mo2-δδ*), resulting in the populated MLCT states in these molecular systems exhibiting either extremely weak emission or being non-emissive. The influence of ligand variation on the dynamics of MLCT states was examined using femtosecond transient absorption spectroscopy, with deactivation time constants determined to be 1.9 ps for [Mo2]-ph, 6.5 ps for [Mo2]-naph, and 49 ps for [Mo2]-anth. This electron transfer behaviour follows an inverse energy-gap law, contrary to the general guideline that applies to the decay of the MLCT state back to the electronic ground state. This result offers valuable insights into understanding the photochemical and photophysical properties of covalently bonded dimetal complexes.

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