Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nature ; 621(7980): 868-876, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37674077

RESUMO

Immune checkpoint blockade (ICB) benefits some patients with triple-negative breast cancer, but what distinguishes responders from non-responders is unclear1. Because ICB targets cell-cell interactions2, we investigated the impact of multicellular spatial organization on response, and explored how ICB remodels the tumour microenvironment. We show that cell phenotype, activation state and spatial location are intimately linked, influence ICB effect and differ in sensitive versus resistant tumours early on-treatment. We used imaging mass cytometry3 to profile the in situ expression of 43 proteins in tumours from patients in a randomized trial of neoadjuvant ICB, sampled at three timepoints (baseline, n = 243; early on-treatment, n = 207; post-treatment, n = 210). Multivariate modelling showed that the fractions of proliferating CD8+TCF1+T cells and MHCII+ cancer cells were dominant predictors of response, followed by cancer-immune interactions with B cells and granzyme B+ T cells. On-treatment, responsive tumours contained abundant granzyme B+ T cells, whereas resistant tumours were characterized by CD15+ cancer cells. Response was best predicted by combining tissue features before and on-treatment, pointing to a role for early biopsies in guiding adaptive therapy. Our findings show that multicellular spatial organization is a major determinant of ICB effect and suggest that its systematic enumeration in situ could help realize precision immuno-oncology.


Assuntos
Imunoterapia , Linfócitos T , Neoplasias de Mama Triplo Negativas , Humanos , Linfócitos B/imunologia , Biópsia , Linfócitos T CD8-Positivos/imunologia , Granzimas/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos CD15/metabolismo , Terapia Neoadjuvante , Medicina de Precisão , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Linfócitos T/imunologia , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/terapia
2.
Proc Natl Acad Sci U S A ; 121(11): e2318320121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38457518

RESUMO

Coordinated carbon and nitrogen metabolism is crucial for bacteria living in the fluctuating environments. Intracellular carbon and nitrogen homeostasis is maintained by a sophisticated network, in which the widespread signaling protein PII acts as a major regulatory hub. In cyanobacteria, PII was proposed to regulate the nitrate uptake by an ABC (ATP-binding cassette)-type nitrate transporter NrtABCD, in which the nucleotide-binding domain of NrtC is fused with a C-terminal regulatory domain (CRD). Here, we solved three cryoelectron microscopy structures of NrtBCD, bound to nitrate, ATP, and PII, respectively. Structural and biochemical analyses enable us to identify the key residues that form a hydrophobic and a hydrophilic cavity along the substrate translocation channel. The core structure of PII, but not the canonical T-loop, binds to NrtC and stabilizes the CRD, making it visible in the complex structure, narrows the substrate translocation channel in NrtB, and ultimately locks NrtBCD at an inhibited inward-facing conformation. Based on these results and previous reports, we propose a putative transport cycle driven by NrtABCD, which is allosterically inhibited by PII in response to the cellular level of 2-oxoglutarate. Our findings provide a distinct regulatory mechanism of ABC transporter via asymmetrically binding to a signaling protein.


Assuntos
Cianobactérias , Transportadores de Nitrato , Nitratos/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Alostérica , Microscopia Crioeletrônica , Cianobactérias/metabolismo , Trifosfato de Adenosina/metabolismo , Nitrogênio/metabolismo , Carbono/metabolismo , Proteínas PII Reguladoras de Nitrogênio/genética , Proteínas PII Reguladoras de Nitrogênio/metabolismo
3.
Plant Physiol ; 194(3): 1498-1511, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-37956105

RESUMO

Drought and heat stresses usually occur concomitantly in nature, with increasing frequency and intensity of both stresses expected due to climate change. The synergistic agricultural impacts of these compound climate extremes are much greater than those of the individual stresses. However, the mechanisms by which drought and heat stresses separately and concomitantly affect dynamic photosynthesis have not been thoroughly assessed. To elucidate this, we used tomato (Solanum lycopersicum) seedlings to measure dynamic photosynthesis under individual and compound stresses of drought and heat. Individual drought and heat stresses limited dynamic photosynthesis at the stages of diffusional conductance to CO2 and biochemistry, respectively. However, the primary limiting factor for photosynthesis shifted to mesophyll conductance under the compound stresses. Compared with the control, photosynthetic carbon gain in fluctuating light decreased by 38%, 73%, and 114% under the individual drought, heat, and compound stresses, respectively. Therefore, compound stresses caused a greater reduction in photosynthetic carbon gain in fluctuating light conditions than individual stress. These findings highlight the importance of mitigating the effects of compound climate extremes on crop productivity by targeting mesophyll conductance and improving dynamic photosynthesis.


Assuntos
Secas , Solanum lycopersicum , Agricultura , Carbono , Mudança Climática , Fotossíntese
4.
Psychosom Med ; 86(3): 202-209, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588496

RESUMO

OBJECTIVE: Major depressive disorder (MDD) is a severe psychiatric symptom worldwide, and the coexistence of MDD with metabolic syndrome (MetS) is common in clinical practice. However, gender differences in comorbid MetS in first-episode and drug-naïve (FEDN) MDD patients have not been reported. Here, we explored potential gender differences in the prevalence and clinical correlates of comorbid MetS in FEDN MDD patients. METHODS: A cross-sectional study of 1718 FEDN MDD patients was conducted. Demographic and clinical data were collected. The Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale, and Positive and Negative Syndrome Scale positive subscale were used to evaluate depression, anxiety, and psychotic symptoms, respectively. RESULTS: The prevalence of MetS was 1.645-fold higher in female MDD patients (38.50%) than in male patients (26.53%). Patients with MetS had higher HAMD score, Hamilton Anxiety Scale score, and Positive and Negative Syndrome Scale positive subscale score than patients without MetS (p values < .001). Furthermore, suicide attempts (male: odds ratio [OR] = 1.706, p = .034; female: OR = 1.639, p = .004) and HAMD score (male: OR = 1.251, p < .001; female: OR = 1.148, p < .001) were independently associated with MetS in male and female patients, whereas age of onset was independently associated with MetS only in female patients (OR = 1.744, p = .047). CONCLUSIONS: Our findings suggest significant gender differences in the prevalence and clinical correlates of comorbid MetS in FEDN MDD patients. Clinical variables (suicide attempts and HAMD scores) may be independently associated with MetS in MDD patients.


Assuntos
Transtorno Depressivo Maior , Síndrome Metabólica , Humanos , Masculino , Feminino , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/diagnóstico , Síndrome Metabólica/epidemiologia , Prevalência , Estudos Transversais , Fatores Sexuais
5.
BMC Geriatr ; 24(1): 15, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177993

RESUMO

BACKGROUND: Subclinical hypothyroidism (SCH) is highly correlated with major depressive disorder (MDD). However, the prevalence and risk factors for SCH in older patients with MDD have rarely been reported in China. METHODS: This cross-sectional study included 266 older MDD patients with SCH was performed. Clinical and anthropometric, biochemical, and thyroid function data were collected. Depression, anxiety, and psychotic symptoms were assessed using the Hamilton Depression Scale, the Hamilton Anxiety Scale, and the Positive and Negative Syndrome Scale positive subscale, respectively. RESULTS: Among older patients with MDD, the prevalence of SCH was 64.7% (172/266). Compared to patients without SCH, older MDD patients with SCH had a longer disease course and higher TSH, A-TG, A-TPO, HDL-C, LDL-C, TC, FPG, and systolic pressure levels (all P ≤ 0.002). Furthermore, disease progression (OR 1.082, 95% CI 1.020-1.147, P = 0.009), A-TG (OR 1.005, 95% CI 1.001-1.009, P = 0.017), TC (OR 2.024, 95% CI 1.213-3.377, P = 0.007), FPG (OR 2.916, 95% CI 1.637-5.194, P < 0.001), systolic pressure (OR 1.053, 95% CI 1.008-1.100, P = 0.022) were independently associated with SCH, in older patients with MDD. CONCLUSIONS: Our findings suggest a high prevalence of SCH in older patients with MDD. Several demographic and clinical variables were independently associated with SCH in older patients with MDD.


Assuntos
Transtorno Depressivo Maior , Hipotireoidismo , Humanos , Idoso , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Prevalência , Estudos Transversais , Hipotireoidismo/diagnóstico , Hipotireoidismo/epidemiologia , Fatores de Risco
6.
J Virol ; 96(6): e0201121, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35201897

RESUMO

Genetically-characterizing full-length HIV-1 RNA is critical for identifying genetically-intact genomes and for comparing these RNA genomes to proviral DNA. We have developed a method for sequencing plasma-derived RNA using long-range sequencing (PRLS assay; ∼8.3 kb from gag to the 3' end or ∼5 kb from integrase to the 3' end). We employed the gag-3' PRLS assay to sequence HIV-1 RNA genomes from ART-naive participants during acute/early infection (n = 6) or chronic infection (n = 2). On average, only 65% of plasma-derived genomes were genetically-intact. Defects were found in all genomic regions but were concentrated in env and pol. We compared these genomes to near-full-length proviral sequences from paired peripheral blood mononuclear cell (PBMC) samples for the acute/early group and found that near-identical (>99.98% identical) sequences were identified only during acute infection. For three participants who initiated therapy during acute infection, we used the int-3' PRLS assay to sequence plasma-derived genomes from an analytical treatment interruption and identified 100% identical genomes between pretherapy and rebound time points. The PRLS assay provides a new level of sensitivity for understanding the genetic composition of plasma-derived HIV-1 RNA from viremic individuals either pretherapy or after treatment interruption, which will be invaluable in assessing possible HIV-1 curative strategies. IMPORTANCE We developed novel plasma-derived RNA using long-range sequencing assays (PRLS assay; 8.3 kb, gag-3', and 5.0 kb, int-3'). Employing the gag-3' PRLS assay, we found that 26% to 51% of plasma-derived genomes are genetically-defective, largely as a result of frameshift mutations and deletions. These genetic defects were concentrated in the env region compared to gag and pol, likely a reflection of viral immune escape in env during untreated HIV-1 infection. Employing the int-3' PRLS assay, we found that analytical treatment interruption (ATI) plasma-derived sequences were identical and genetically-intact. Several sequences from the ATI plasma samples were identical to viral sequences from pretherapy plasma and PBMC samples, indicating that HIV-1 reservoirs established prior to therapy contribute to viral rebound during an ATI. Therefore, near-full-length sequencing of HIV-1 particles is required to gain an accurate picture of the genetic landscape of plasma HIV-1 virions in studies of HIV-1 replication and persistence.


Assuntos
Genoma Viral , Soropositividade para HIV , HIV-1 , Antirretrovirais/uso terapêutico , Soropositividade para HIV/virologia , HIV-1/genética , Humanos , Leucócitos Mononucleares , Provírus/genética , RNA Viral/sangue , Vírion/genética
7.
J Virol ; 96(16): e0058822, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35916523

RESUMO

Co-infection with hepatitis B (HBV) and human immunodeficiency virus (HIV) increases overall and liver-related mortality. In order to identify interactions between these two viruses in vivo, full-length HIV proviruses were sequenced from a cohort of HIV-HBV co-infected participants and from a cohort of HIV mono-infected participants recruited from Bangkok, Thailand, both before the initiation of antiretroviral therapy (ART) and after at least 2 years of ART. The co-infected individuals were found to have higher levels of genetically-intact HIV proviruses than did mono-infected individuals pre-therapy. In these co-infected individuals, higher levels of genetically-intact HIV proviruses or proviral genetic-diversity were also associated with higher levels of sCD14 and CXCL10, suggesting that immune activation is linked to more genetically-intact HIV proviruses. Three years of ART decreased the overall level of HIV proviruses, with fewer genetically-intact proviruses being identified in co-infected versus mono-infected individuals. However, ART increased the frequency of certain genetic defects within proviruses and the expansion of identical HIV sequences. IMPORTANCE With the increased availability and efficacy of ART, co-morbidities are now one of the leading causes of death in HIV-positive individuals. One of these co-morbidities is co-infection with HBV. However, co-infections are still relatively understudied, especially in countries where such co-infections are endemic. Furthermore, these countries have different subtypes of HIV circulating than the commonly studied HIV subtype B. We believe that our study serves this understudied niche and provides a novel approach to investigating the impact of HBV co-infection on HIV infection. We examine co-infection at the molecular level in order to investigate indirect associations between the two viruses through their interactions with the immune system. We demonstrate that increased immune inflammation and activation in HBV co-infected individuals is associated with higher HIV viremia and an increased number of genetically-intact HIV proviruses in peripheral blood cells. This leads us to hypothesize that inflammation could be a driver in the increased mortality rate of HIV-HBV co-infected individuals.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Inflamação/virologia , Coinfecção/patologia , Coinfecção/virologia , DNA Viral/genética , Infecções por HIV/complicações , Infecções por HIV/patologia , Infecções por HIV/virologia , Hepatite B/complicações , Hepatite B/patologia , Hepatite B/virologia , Vírus da Hepatite B/fisiologia , Humanos , Provírus/genética , Tailândia/epidemiologia , Viremia/virologia
8.
Oral Dis ; 27(6): 1487-1497, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33031609

RESUMO

OBJECTIVE: Experiments were performed to evaluate CYLD expression in human gingival tissue samples and to examine the effects of CYLD on inflammatory responses in lipopolysaccharide (LPS)- or TNF-α-stimulated human gingival fibroblasts (HGFs). METHODS: Immunohistochemistry for CYLD and p65 expression was performed with healthy and inflamed gingival tissue samples. siRNA was used to knock down the expression of CYLD in HGFs. Upon LPS or TNF-α stimulation, NF-κB activation was detected in control and CYLD-knockdown HGFs. RT-PCR was applied to determine gene expression. Western blot analyses were employed to assess protein expression. Immunofluorescence staining was carried out to evaluate the nuclear translocation of p65. RESULTS: Immunohistochemical staining showed the expression of CYLD in human gingival tissues. In addition, CYLD protein expression was reduced in inflamed gingival tissue samples compared with healthy tissue samples. CYLD knockdown greatly enhanced the mRNA expression of proinflammatory cytokines in LPS- or TNF-α-stimulated HGFs. Furthermore, knocking down CYLD expression increased LPS-stimulated NF-κB activation in HGFs. Unexpectedly, CYLD knockdown did not affect TNF-α-induced NF-κB activation. CONCLUSIONS: Our results suggest that CYLD participates in periodontal inflammatory responses by negatively regulating LPS-induced NF-κB signalling.


Assuntos
Enzima Desubiquitinante CYLD , Fibroblastos , Gengiva , Células Cultivadas , Enzimas Desubiquitinantes , Humanos , Lipopolissacarídeos , NF-kappa B
9.
J Cell Biochem ; 121(8-9): 3764-3779, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31680325

RESUMO

The apoptosis of human periodontal ligament cells (HPDLCs) may be an important factor of the negative effect of advanced glycation end products (AGEs) on the periodontal tissue of diabetic patients. However, the pathways or potential effects of apoptosis in AGEs-treated HPDLCs have not been fully elucidated. Autophagy is closely related to apoptosis. Herein, we investigated the potential mechanism of apoptosis and autophagy in HPDLCs treated with AGEs via an in vitro model. We found that AGEs-treated HPDLCs showed a time- and concentration-dependent reduction in the cell survival rate. The mitochondrial-dependent apoptosis was induced in AGEs-treated HPDLCs, as confirmed by the mitochondrial membrane potential depolarization, decreased Bcl-2 expression, increased Bax expression, and increased caspase-3 and PARP cleavage. Autophagy was also induced in AGEs-treated HPDLCs, as indicated by the conversion of LC3-II/LC3-I and the presence of autophagosomes. Interestingly, our study results suggested that apoptosis and autophagy were related to reactive oxygen species (ROS) production. In addition, AGEs-induced autophagy acted as a latent factor in decreasing the generation of ROS in HPDLCs and protecting against the AGEs-induced apoptosis. In summary, our study shows that ROS are essential in AGEs-induced HPDLCs apoptosis and autophagy, which may be a molecular mechanism for the repairment of ROS-induced damage in HPDLCs treated with AGEs to promote cell survival. The present study might provide new insights into the therapeutic targeting of HPDLCs autophagy, which could be an additional strategy for periodontitis in patients with diabetes mellitus.

10.
Appl Opt ; 58(4): 1146-1151, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874165

RESUMO

We disclose a method of fabricating a low-voltage-driven smart glass based on micro-patterned liquid crystal (LC) Fresnel lenses and implement three proof-of-concept prototypes. Distinct from the conventional LC-based smart windows with the scattering state, the prominence of our proposed LC smart glass in blurry state under both normal and oblique observations stems from the image distortion caused by LC Fresnel lenses. In addition, the high transmittance (>90%) in clear state is obtained by applying a low voltage of 2 V to each prototype. Moreover, by elaborating the design of the LC smart glass, the reversed switching states [i.e., a clear (voltage OFF) state and a blurry (voltage ON) state] and fast switching time can be simultaneously achieved.

11.
Oral Dis ; 25(8): 1972-1982, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31361069

RESUMO

OBJECTIVE: Macrophages could be fully polarized and acquire specific phenotype like M1, which considered to be essential for the alveolar bone destruction during the development of periodontitis. However, the molecular mechanisms underlying the effects of M1 macrophages on the alveolar bone destruction are still not clear yet. METHODS: Mouse periodontitis model was established to determine the involvement of M1 macrophages in the pathogenic process. Condition medium of the M1 macrophages (M1-CM) was incubated with pre-osteoblasts to evaluate its effects on the osteoblastogenesis. Cells after treatment with CM were used for RNA-sequencing, quantitative PCR, Western blotting, and immunofluorescence staining to figure out pathways involved in the inhibition of osteoblastogenesis. RESULTS: Increased infiltration of M1 macrophages was associated with alveolar bone destruction in periodontitis. M1-CM markedly suppressed the generation of osteoblasts as evidenced by decreased expressions of Runx2 and Ocn, as well as reduced activity of ALP. Interestingly, RNA-sequencing indicated the activation of TLR4/AP1 signaling pathway in pre-osteoblasts treated with CM. Inhibition of TLR4 reduced the translocation of AP1 and rescued the osteoblastogenesis reduced by M1-CM. CONCLUSION: M1 macrophages induce TLR4/AP1 signaling of pre-osteoblasts to inhibit the osteoblastogenesis via paracrine, at least partially contributing to alveolar bone destruction in periodontitis.


Assuntos
Perda do Osso Alveolar , Macrófagos/metabolismo , Periodontite , Receptor 4 Toll-Like , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/patologia , Animais , Camundongos , Osteoblastos , Periodontite/tratamento farmacológico , Periodontite/patologia , Transdução de Sinais
12.
Retrovirology ; 15(1): 3, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29316955

RESUMO

Antiretroviral therapy effectively suppresses, but does not eradicate HIV-1 infection. Persistent low-level HIV-1 can still be detected in plasma and cellular reservoirs even after years of effective therapy, and cessation of current treatments invariably results in resumption of viral replication. Efforts to eradicate persistent HIV-1 require a comprehensive examination of the quantity and genetic composition of HIV-1 within the plasma and infected cells located in the peripheral blood and tissues throughout the body. Single-molecule techniques, such as the single-copy assay and single-genome/proviral sequencing assays, have been employed to further our understanding of the source and viral dynamics of persistent HIV-1 during long-term effective therapy. The application of the single-copy assay, which quantifies plasma HIV-1 RNA down to a single copy, has revealed that viremia persists in the plasma and CSF after years of effective therapy. This low-level HIV-1 RNA also persists in the plasma following treatment intensification, treatment with latency reversing agents, cancer-related therapy, and bone marrow transplantation. Single-genome/proviral sequencing assays genetically characterise HIV-1 populations after passing through different selective pressures related to cell type, tissue type, compartment, or therapy. The application of these assays has revealed that the intracellular HIV-1 reservoir is stable and mainly located in CD4+ memory T cells. Moreover, this intracellular HIV-1 reservoir is primarily maintained by cellular proliferation due to homeostasis and antigenic stimulation, although cryptic replication may take place in anatomic sites where treatment is sub-optimal. The employment of single-genome/proviral sequencing showed that latency reversing agents broadly activate quiescent proviruses but do not clear the intracellular reservoir. Recently, full-length individual proviral sequencing assays have been developed and the application of these assays has revealed that the majority of intracellular HIV-1 DNA is genetically defective. In addition, the employment of these assays has shown that genetically intact proviruses are unequally distributed in memory T cell subsets during antiretroviral therapy. The application of single-molecule assays has enhanced the understanding of the source and dynamics of persistent HIV-1 in the plasma and cells of HIV-infected individuals. Future studies of the persistent HIV-1 reservoir and new treatment strategies to eradicate persistent virus will benefit from the utilization of these assays.


Assuntos
Infecções por HIV/virologia , HIV-1/isolamento & purificação , Provírus/isolamento & purificação , Carga Viral/métodos , Viremia/virologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/sangue , Infecções por HIV/imunologia , HIV-1/genética , HIV-1/fisiologia , Humanos , Provírus/genética , Provírus/fisiologia , RNA Viral/análise , RNA Viral/sangue , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real
13.
Phytother Res ; 32(12): 2447-2455, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30159926

RESUMO

Cancer stem cells (CSCs) are considered to play essential roles in the process of origination, proliferation, migration, and invasion of cancer, and their properties are regulated by Wnt/ß-catenin pathway. Phenethyl isothiocyanate (PEITC) is a natural product obtained from cruciferous vegetables with anticancer activities. The present study aimed to investigate the inhibitory effect and the underlying mechanisms of PEITC on colorectal CSCs. In this study, we found that PEITC can significantly reduce the size and number of colorectal cancer cell spheroids in serum-free medium. With increasing PEITC concentrations (10-40 µM), the number of spheroids was reduced to about 10% of the control group, and the percentage of CD133+ cells was decreased by about 3-16 folds. PEITC also decreased the expression of CSC markers. Meanwhile, inhibition of proliferation as well as induction of apoptosis of colorectal CSCs was observed after PEITC treatment. Furthermore, through activating Wnt/ß-catenin pathway with LiCl, the inhibitory effects of PEITC on colorectal CSCs were diminished. Our data suggested that PEITC can be an effective inhibitor of colorectal CSCs by targeting Wnt/ß-catenin pathway.


Assuntos
Neoplasias Colorretais/patologia , Isotiocianatos/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo
14.
Apoptosis ; 22(6): 841-851, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28247205

RESUMO

Cytolethal distending toxin (CDT) which is produced by Aggregatibacter actinomycetemcomitans causes apoptosis in lymphocytes. But the specific mechanism is not clear. The aim of our research was to investigate the effect and mechanism during this process. The wild-type CdtA, CdtB, CdtC (CdtAW, CdtBW, CdtCW) and mutant CdtB (CdtBM) were expressed and purified respectively and the purity of each subunit was examined by BandScan software. And the type I deoxyribonuclease and PI-3,4,5-triphosphate (PI-3,4,5-P3, PIP3) phosphatase activity were detected by DNA agarose gel electrophoresis and enzyme-linked immunosorbent assay respectively. The cell apoptosis rates were analyzed by flow cytometry. The morphological changes of apoptosis cells were observed by confocal laser scanning microscopy. The protein expression of Bax and Bcl-2 was examined by western blot. Differentially expressed apoptosis-related proteins were identified based on isobaric tags for relative and absolute quantitation technology. In the present study we found that: (i) recombinant wild-type CdtA, CdtB and CdtC (CdtAW, CdtBW, CdtCW) and mutant CdtB (CdtBM) were correctly expressed and the purity of each protein was higher than 80%, (ii) the average apoptosis rate in wild-type CDT (CDTW) treated groups was 50.54%, which was significantly higher than the controls (4.71%) and mutant CDT (CDTM) treated groups (5.58%) (p < 0.05), (iii) morphological changes of apoptosis were observed in CDTW treated cells, (iv) the expression of Bax protein was significantly increased in CDTW treated cells, while Bcl-2 protein expression was significantly decreased, (v) 17 apoptosis-related proteins were expressed differentially, among which 10 proteins (SMNDC1, TNFRSF10B, UBE2I, ITM2A, CASP3, P53, EIF1, TCF3, HMGN5, CASP8) were up-regulated and 7 proteins (RRM2, TPX2, KIF11, NUCKS1, TOP2A, XRCC1, PTPLAD1, RRM2) were down-regulated, (vi) one possible apoptotic pathway [Ubc9 (UBE2I)/P53/DR5 (TNFRSF10B)/Caspase-8 (CASP8)/ Caspase-3 (CASP3)] was selected and partially proved.


Assuntos
Apoptose/efeitos dos fármacos , Toxinas Bacterianas/toxicidade , Desoxirribonuclease I/metabolismo , Humanos , Marcação por Isótopo , Células Jurkat , Modelos Biológicos , Fosfoproteínas Fosfatases/metabolismo , Subunidades Proteicas/metabolismo , Proteômica , Reprodutibilidade dos Testes , Proteína X Associada a bcl-2/metabolismo
15.
Phytother Res ; 31(4): 680-688, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28198062

RESUMO

Cancer stem cells (CSCs) are highly implicated in the progression of human cancers. Thus, targeting CSCs may be a promising strategy for cancer therapy. Wnt/ß-catenin and Sonic Hedgehog pathways play an important regulatory role in maintaining CSC characteristics. Natural compounds, such as curcumin, possess chemopreventive properties. However, the interventional effect of curcumin on lung CSCs has not been clarified. In the present study, tumorsphere formation assay was used to enrich lung CSCs from A549 and H1299 cells. We showed that the levels of lung CSC markers (CD133, CD44, ALDHA1, Nanog and Oct4) and the number of CD133-positive cells were significantly elevated in the sphere-forming cells. We further illustrated that curcumin efficiently abolished lung CSC traits, as evidenced by reduced tumorsphere formation, reduced number of CD133-positive cells, decreased expression levels of lung CSC markers, as well as proliferation inhibition and apoptosis induction. Moreover, we demonstrated that curcumin suppressed the activation of both Wnt/ß-catenin and Sonic Hedgehog pathways. Taken together, our data suggested that curcumin exhibited its interventional effect on lung CSCs via inhibition of Wnt/ß-catenin and Sonic Hedgehog pathways. These novel findings could provide new insights into the potential therapeutic application of curcumin in lung CSC elimination and cancer intervention. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Curcumina/uso terapêutico , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Via de Sinalização Wnt/genética , Apoptose , Proliferação de Células/efeitos dos fármacos , Curcumina/administração & dosagem , Curcumina/farmacologia , Humanos , Transdução de Sinais
16.
Opt Lett ; 41(24): 5668-5671, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27973485

RESUMO

In this Letter, we disclose a Dammann grating (DG) based on the hybrid photo-aligned nematic liquid crystals (LCs). The LC cell is composed of two substrates, wherein the first substrate is treated to provide the homeotropic alignment, and the other substrate is set to provide an in-plane, patterned alignment with a mutually orthogonal easy axis in the neighboring alignment domains. Thus, the fabricated polarization independent DG generates an optical array of equally distributed energy, which is characterized by a diffraction efficiency of more than 58%, a response time <1 ms, and the driving voltage 3 V/µm. Furthermore, the optically active alignment layer provides the optical tunability and reconfigurability for the proposed DG. With these advantageous parameters, these DGs can be applied in modern applications.

17.
Arch Gynecol Obstet ; 293(6): 1339-45, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27022933

RESUMO

OBJECTIVE: To assess the correlation between serum 25-hydroxy vitamin D [25(OH)D] status and outcomes of in vitro fertilization (IVF) in infertile women through review systematically. METHODS: We used Embase, Pubmed, and Cochrane database to identify all studies that assessed the correlation between serum vitamin D levels and IVF outcomes in infertile women up until 30 June 2015, with the restricted language of English. We included studies that compared IVF outcomes between infertile women vitamin D <20 ng/ml and vitamin D ≥20 ng/ml. The results were summarized using Stata 12.0 software. For studies reported dichotomous outcomes (clinical pregnancy rate and live birth rate), we pooled the relative risks ratios (RRs) and 95 % confidence intervals (CIs) in a random effects model. RESULTS: Our search resulted in the retrieval and screening of 134 studies. Of those, five studies were included in our meta-analysis. The risk for lower clinical pregnancy rate was not significantly increased in the deficient group (RR 0.88, 95 % CI 0.69-1.11). Lower vitamin D status was associated with lower live birth rate (RR 0.76, 95 % CI 0.61-0.93). CONCLUSION: There is no significant correlation between deficient serum vitamin D level and lower clinical pregnancy rate in infertile woman undergoing in vitro fertilization. On the other hand, deficient vitamin D level was related to lower live birth rate.


Assuntos
Fertilização in vitro , Infertilidade Feminina/complicações , Taxa de Gravidez , Vitamina D/análogos & derivados , Vitaminas/sangue , Feminino , Humanos , Infertilidade Feminina/sangue , Gravidez , Vitamina D/sangue
18.
Int J Mol Sci ; 17(6)2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27338352

RESUMO

RNAs have been shown to exhibit differential enrichment between nuclear, cytoplasmic, and exosome fractions. A current fundamental question asks why non-coding RNA partition into different spatial compartments. We report on the analysis of cellular compartment models with miRNA data sources for spatial-mechanistic modeling to address the broad area of multi-scalar cellular communication by miRNAs. We show that spatial partitioning of miRNAs is related to sequence similarity to the overall transcriptome. This has broad implications in biological informatics for gene regulation and provides a deeper understanding of nucleotide sequence structure and RNA language meaning for human pathologies resulting from changes in gene expression.


Assuntos
MicroRNAs/genética , Homologia de Sequência do Ácido Nucleico , Transcriptoma , Biologia Computacional/métodos , Bases de Dados de Ácidos Nucleicos , Exossomos/genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , MicroRNAs/química , Modelos Biológicos
19.
Plant Physiol Biochem ; 207: 108426, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38340689

RESUMO

In nature, light intensity usually fluctuates and a sudden shade-sun transition can induce photodamage to photosystem I (PSI) in many angiosperms. Photosynthetic regulation in fluctuating light (FL) has been studied extensively in C3 plants; however, little is known about how C4 plants cope FL to prevent PSI photoinhibition. We here compared photosynthetic responses to FL between maize (Zea mays, C4) and tomato (Solanum lycopersicum, C3) grown under full sunlight. Maize leaves had significantly higher cyclic electron flow (CEF) activity and lower photorespiration activity than tomato. Upon a sudden shade-sun transition, maize showed a significant stronger transient PSI over-reduction than tomato, resulting in a significant greater PSI photoinhibition in maize after FL treatment. During the first seconds upon shade-sun transition, CEF was stimulated in maize at a much higher extent than tomato, favoring the rapid formation of trans-thylakoid proton gradient (ΔpH), which was helped by a transient down-regulation of chloroplast ATP synthase activity. Therefore, modulation of ΔpH by regulation of CEF and chloroplast ATP synthase adjusted PSI redox state at donor side, which partially compensated for the deficiency of photorespiration. We propose that C4 plants use different photosynthetic strategies for coping with FL as compared with C3 plants.


Assuntos
Complexo de Proteína do Fotossistema I , Zea mays , Complexo de Proteína do Fotossistema I/metabolismo , Zea mays/metabolismo , ATPases de Cloroplastos Translocadoras de Prótons , Fotossíntese/fisiologia , Luz , Transporte de Elétrons , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/metabolismo
20.
Microbiol Spectr ; 12(6): e0029824, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38695606

RESUMO

The cyanosiphophage Mic1 specifically infects the bloom-forming Microcystis aeruginosa FACHB 1339 from Lake Chaohu, China. Previous genomic analysis showed that its 92,627 bp double-stranded DNA genome consists of 98 putative open reading frames, 63% of which are of unknown function. Here, we investigated the transcriptome dynamics of Mic1 and its host using RNA sequencing. In the early, middle, and late phases of the 10 h lytic cycle, the Mic1 genes are sequentially expressed and could be further temporally grouped into two distinct clusters in each phase. Notably, six early genes, including gp49 that encodes a TnpB-like transposase, immediately reach the highest transcriptional level in half an hour, representing a pioneer cluster that rapidly regulates and redirects host metabolism toward the phage. An in-depth analysis of the host transcriptomic profile in response to Mic1 infection revealed significant upregulation of a polyketide synthase pathway and a type III-B CRISPR system, accompanied by moderate downregulation of the photosynthesis and key metabolism pathways. The constant increase of phage transcripts and relatively low replacement rate over the host transcripts indicated that Mic1 utilizes a unique strategy to gradually take over a small portion of host metabolism pathways after infection. In addition, genomic analysis of a less-infective Mic1 and a Mic1-resistant host strain further confirmed their dynamic interplay and coevolution via the frequent horizontal gene transfer. These findings provide insights into the mutual benefit and symbiosis of the highly polymorphic cyanobacteria M. aeruginosa and cyanophages. IMPORTANCE: The highly polymorphic Microcystis aeruginosa is one of the predominant bloom-forming cyanobacteria in eutrophic freshwater bodies and is infected by diverse and abundant cyanophages. The presence of a large number of defense systems in M. aeruginosa genome suggests a dynamic interplay and coevolution with the cyanophages. In this study, we investigated the temporal gene expression pattern of Mic1 after infection and the corresponding transcriptional responses of its host. Moreover, the identification of a less-infective Mic1 and a Mic1-resistant host strain provided the evolved genes in the phage-host coevolution during the multiple-generation cultivation in the laboratory. Our findings enrich the knowledge on the interplay and coevolution of M. aeruginosa and its cyanophages and lay the foundation for the future application of cyanophage as a potential eco-friendly and bio-safe agent in controlling the succession of harmful cyanobacterial blooms.


Assuntos
Bacteriófagos , Microcystis , Microcystis/virologia , Microcystis/genética , Microcystis/metabolismo , Bacteriófagos/genética , Bacteriófagos/fisiologia , China , Transcriptoma , Lagos/microbiologia , Lagos/virologia , Genoma Viral/genética , Evolução Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA