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1.
J Immunol ; 209(8): 1492-1498, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36165173

RESUMO

Underexpression of p53 is considered the leading cause of the decreased miR-1246 expression in B cells of systemic lupus erythematosus (SLE) patients, yet the exact mechanism of action still remains unclear. To further explore the molecular mechanism of p53 upregulating miR-1246 expression, we targeted the methylation and acetylation of histone H3 in the miR-1246 promoter region of SLE B cells. We found that increased histone H3 trimethylation at Lys27 (H3K27me3) and decreased histone H3 acetylation at Lys9 and Lys14 (H3K9/K14ac) in the miR-1246 promoter region are essential for the low expression of miR-1246 in SLE B cells. p53 can promote miR-1246 transcription by recruiting Jumonji domain-containing protein 3 (JMJD3), E1A-binding protein p300 (EP300), and CREB-binding protein (CBP) to bind to the miR-1246 promoter, downregulating H3K27me3 and upregulating H3K9/K14ac. Furthermore, early B cell factor 1 (EBF1), CD40, CD38, and X box binding protein-1 (XBP-1) expression levels in SLE B cells transfected with p53 expression plasmid were significantly decreased, whereas autoantibody IgG production in autologous CD4+ T cells cocultured with overexpressed p53 SLE B cells was reduced. Collectively, our data suggest that the reduction of p53 decreases miR-1246 expression via upregulation of H3K27me3 and downregulation of H3K9/14ac, which in turn results in SLE B cell hyperactivity.


Assuntos
Linfócitos B , Lúpus Eritematoso Sistêmico , MicroRNAs , Proteína Supressora de Tumor p53 , Proteína de Ligação a CREB/metabolismo , Histonas/metabolismo , Humanos , Imunoglobulina G/metabolismo , Lúpus Eritematoso Sistêmico/genética , MicroRNAs/genética , Proteína Supressora de Tumor p53/genética
2.
Clin Lab ; 70(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38747921

RESUMO

BACKGROUND: Pseudothrombocytopenia (PTCP) can be caused by anticoagulants or pre-analytical issues. The authors present a case of PTCP attributed to pre-analytical issues in a 68-year-old male patient. METHODS: The platelet count results were obtained using both the impedance and fluorescence channels of Sysmex XN-10. The blood film was scanned using both Cellavision DM96 and a microscope. RESULTS: The flag for PLT-Clumps and the scattergram from the PLT-F channel indicated the presence of platelet aggregation. Fibrin could be observed at the feathered end of the blood film. A diagnosis of PTCP resulting from pre-analytical issues was made. CONCLUSIONS: The presence of fibrin in a blood film is a critical indicator for diagnosing PTCP due to pre-analytical issues.


Assuntos
Fibrina , Trombocitopenia , Humanos , Anticoagulantes , Plaquetas , Fibrina/metabolismo , Fibrina/análise , Agregação Plaquetária , Contagem de Plaquetas/métodos , Trombocitopenia/sangue , Trombocitopenia/diagnóstico , Masculino , Idoso
3.
Artif Organs ; 48(8): 839-848, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38660762

RESUMO

BACKGROUND: Vascular smooth muscle cells (VSMCs) are commonly used as seed cells in tissue-engineered vascular constructions. However, their variable phenotypes and difficult to control functions pose challenges. This study aimed to overcome these obstacles using a three-dimensional culture system. METHODS: Calf VSMCs were administered tumor necrosis factor-alpha (TNF-α) before culturing in two- and three-dimensional well plates and polyglycolic acid (PGA) scaffolds, respectively. The phenotypic markers of VSMCs were detected by immunofluorescence staining and western blotting, and the proliferation and migration abilities of VSMCs were detected by CCK-8, EDU, cell counting, scratch, and Transwell assays. RESULTS: TNF-α rapidly decreased the contractile phenotypic markers and elevated the synthetic phenotypic markers of VSMCs, as well as markedly increasing the proliferation and migration ability of VSMCs under two- and three-dimensional culture conditions. CONCLUSIONS: TNF-α can rapidly induce a phenotypic shift in VSMCs and change their viability on PGA scaffolds.


Assuntos
Movimento Celular , Proliferação de Células , Sobrevivência Celular , Músculo Liso Vascular , Miócitos de Músculo Liso , Fenótipo , Alicerces Teciduais , Fator de Necrose Tumoral alfa , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Alicerces Teciduais/química , Bovinos , Células Cultivadas , Engenharia Tecidual/métodos , Técnicas de Cultura de Células em Três Dimensões/métodos
4.
Int J Audiol ; 63(3): 207-212, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36662150

RESUMO

OBJECTIVE: This exploratory study examined whether central auditory tests show differences between people living with HIV (PLWH) treated with two predominant antiretroviral drug therapy (ART) regimens. DESIGN: Cross-sectional. STUDY SAMPLE: 253 PLWH (mean age 39.8 years) from the Shanghai Public Health Clinical Centre, China. METHODS: The Hearing in Noise Test speech reception threshold (SRT) assessed central auditory function and the Montreal Cognitive Assessment (MoCA) assessed cognition. The relationship between ART regimen and SRT was evaluated with multivariable linear regression incorporating age, HIV duration, and peripheral hearing ability. Multivariable logistic regression was used to ascertain if SRT and ART regimen predicted MoCA impairment. RESULTS: The two predominant ART regimens differed by one drug (zidovudine or tenofovir). Participants taking the zidovudine-containing regimen had poorer SRT performance (p=.012) independent of age and hearing thresholds. MoCA scores did not differ between drug regimens, but a negative relationship was found between SRT and MoCA impairment (p=.048). CONCLUSIONS: ART regimens differed in their association with central auditory test performance likely reflecting neurocognitive changes in PLWH taking the zidovudine-containing regimen. Central auditory test performance also marginally predicted cognitive impairment, supporting further assessment of central auditory tests to detect neurocognitive deficits in PLWH.


Assuntos
Infecções por HIV , Percepção da Fala , Adulto , Humanos , Zidovudina/uso terapêutico , Estudos Transversais , China , Testes Auditivos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia
5.
Biochem Biophys Res Commun ; 671: 229-235, 2023 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-37307706

RESUMO

The process of erythroid differentiation is orchestrated at the molecular level by a complex network of transcription factors. Erythroid Krüppel-like factor (EKLF/KLF1) is a master erythroid gene regulator that directly regulates most aspects of terminal erythroid differentiation. However, the underlying regulatory mechanisms of EKLF protein stability are still largely unknown. In this study, we identified Vacuolar protein sorting 37 C (VPS37C), a core subunit of the Endosomal sorting complex required for transport-I (ESCRT-I) complex, as an essential regulator of EKLF stability. Our study showed that VPS37C interacts with EKLF and prevents K48-linked polyubiquitination of EKLF and proteasome-mediated EKLF degradation, thus enhancing EKLF protein stability and transcriptional activity. VPS37C overexpression in murine erythroleukemia (MEL) cells promotes hexamethylene bisacetamide (HMBA)-induced erythroid differentiation manifested by up-regulating erythroid-specific EKLF target genes and increasing benzidine-positive cells. In contrast, VPS37C knockdown inhibits HMBA-induced MEL cell erythroid differentiation. Particularly, the restoration of EKLF expression in VPS37C-knockdown MEL cells reverses erythroid-specific gene expression and hemoglobin production. Collectively, our study demonstrated VPS37C is a novel regulator of EKLF ubiquitination and degradation, which plays a positive role in erythroid differentiation of MEL cells by enhancing EKLF protein stability.


Assuntos
Fatores de Transcrição Kruppel-Like , Proteína C , Animais , Camundongos , Proteína C/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Diferenciação Celular/genética , Transporte Proteico , Células Eritroides/metabolismo
6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(5): 818-824, 2023 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-37807734

RESUMO

OBJECTIVE: Constructing a predictive model for urinary incontinence after laparoscopic radical prostatectomy (LRP) based on prostatic gland related MRI parameters. METHODS: In this study, 202 cases were included. All the patients were diagnosed with prostate cancer by prostate biopsy and underwent LRP surgery in Peking University Third Hospital. The preoperative MRI examination of all the patients was completed within 1 week before the prostate biopsy. Prostatic gland related parameters included prostate length, width, height, prostatic volume, intravesical prostatic protrusion length (IPPL), prostate apex shape, etc. From the first month after the operation, the recovery of urinary continence was followed up every month, and the recovery of urinary continence was based on the need not to use the urine pad all day long. Logistic multivariate regression analysis was used to analyze the influence of early postoperative recovery of urinary continence. Risk factors were used to draw the receiver operator characteristic (ROC) curves of each model to predict the recovery of postoperative urinary continence, and the difference of the area under the curve (AUC) was compared by DeLong test, and the clinical net benefit of the model was evaluated by decision curve analysis (DCA). RESULTS: The average age of 202 patients was 69.0 (64.0, 75.5) years, the average prostate specific antigen (PSA) before puncture was 12.12 (7.36, 20.06) µg/L, and the Gleason score < 7 points and ≥ 7 points were 73 cases (36.2%) and 129 cases (63.9%) respectively, with 100 cases (49.5%) at T1/T2 clinical stage, and 102 cases (50.5%) at T3 stage. The prostatic volume measured by preoperative MRI was 35.4 (26.2, 51.1) mL, the ratio of the height to the width was 0.91 (0.77, 1.07), the membranous urethral length (MUL) was 15 (11, 16) mm, and the IPPL was 2 (0, 6) mm. The prostatic apex A-D subtypes were 67 cases (33.2%), 80 cases (39.6%), 24 cases (11.9%) and 31 cases (15.3%), respectively. The training set and validation set were 141 cases and 61 cases, respectively. The operations of all the patients were successfully completed, and the urinary continence rate was 59.4% (120/202) in the 3 months follow-up. The results of multivariate analysis of the training set showed that the MUL (P < 0.001), IPPL (P=0.017) and clinical stage (P=0.022) were independent risk factors for urinary incontinence in the early postoperative period (3 months). The nomogram and clinical decision curve were made according to the results of multivariate analysis. The AUC value of the training set was 0.885 (0.826, 0.944), and the AUC value of the validation set was 0.854 (0.757, 0.950). In the verification set, the Hosmer-Lemeshow goodness-of-fit test was performed on the model, and the Chi-square value was 5.426 (P=0.711). CONCLUSION: Preoperative MUL, IPPL, and clinical stage are indepen-dent risk factors for incontinence after LRP. The nomogram developed based on the relevant parameters of MRI glands can effectively predict the recovery of early urinary continence after LRP. The results of this study require further large-scale clinical research to confirm.


Assuntos
Laparoscopia , Neoplasias da Próstata , Incontinência Urinária , Masculino , Humanos , Próstata/diagnóstico por imagem , Próstata/cirurgia , Prostatectomia/efeitos adversos , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Incontinência Urinária/etiologia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Imageamento por Ressonância Magnética/efeitos adversos , Recuperação de Função Fisiológica , Estudos Retrospectivos
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(5): 843-850, 2023 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-37807738

RESUMO

OBJECTIVE: To investigate the imaging effect of a near-infrared fluorescent targeted probe ICG-NP41 on the neurovascular bundles (NVB) around the prostate in rats. METHODS: A near-infrared fluorescent targeted probe ICG-NP41 was synthesized. An animal model for NVB imaging was established using Sprague-Dawley rats (250-400 g). Experiments were conducted using a custom-built near-infrared windowⅡ(NIR-Ⅱ) small animal in vivo imaging system, and images collected were processed using ImageJ and Origin. The fluorescence signal data were statistically analyzed using GraphPad Prism. The signal-to-background ratio (SBR) for NVB was quantitatively calculated to explore the effective dosage and imaging time points. Finally, paraffin pathology sections and HE staining were performed on the imaging structures. RESULTS: Except for rats in the control group (n=2), right-sided NVB of the rats injected with ICG-NP41 (n=2 per group) were all observed in NIR-Ⅱ fluorescence mode 2 h and 4 h after administration. At 2 h and 4 h, average SBR of cavernous nerve in 2 mg/kg group in fluorescence mode was 1.651±0.142 and 1.619±0.110, respectively, both higher than that in white light mode (1.111±0.036), with no significant difference (P>0.05); average SBR of 4 mg/kg group in fluorescence mode were 1.168±0.066 and 1.219±0.118, respectively, both higher than that in white light mode (1.081±0.040), with no significant difference (P>0.05). At 2 h and 4 h, the average SBR of 2 mg/kg and 4 mg/kg groups in fluorescence mode were higher than that of the control group (SBR=1), the average SBR of the 2 mg/kg group was higher than that of the 4 mg/kg group, and all the above with no significant difference (P>0.05). The average diameter of the nerve measured by full width at half maxima method was about (178±15) µm. HE staining of paraffin sections showed the right major pelvic ganglion. CONCLUSION: The near-infrared fluorescent targeted probe ICG-NP41 can be used for real-time imaging of the NVB around the prostate in rats, providing a potential feasible solution for localizing NVB in real time during nerve-sparing radical prostatectomy.


Assuntos
Parafina , Próstata , Masculino , Ratos , Animais , Próstata/diagnóstico por imagem , Verde de Indocianina , Ratos Sprague-Dawley , Corantes Fluorescentes
8.
Angew Chem Int Ed Engl ; 62(52): e202311451, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37861089

RESUMO

Unlike absorption-based colors of dyes and pigments, reflection-based colors of photonic crystals, so called "structural colors", are responsive to external stimuli, but can remain unfaded for over ten million years, and therefore regarded as a next-generation coloring mechanism. However, it is a challenge to rationally design the spectra of structural colors, where one structure gives only one reflection peak defined by Bragg's law, unlike those of absorption-based colors. Here, we report a reconfigurable photonic crystal that exhibits single-peak and double-peak structural colors. This photonic crystal is composed of a colloidal nanosheet in water, which spontaneously adopts a layered structure with single periodicity (407 nm). After a temperature-gradient treatment, the photonic crystal segregates into two regions with shrunken (385 nm) and expanded (448 nm) periodicities, and thus exhibits double reflection peaks that are blue- and red-shifted from the original one, respectively. Notably, the transition between the single-peak and double-peak states is reversible.

9.
BMC Plant Biol ; 22(1): 371, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35883045

RESUMO

BACKGROUND: Cannabis is an important industrial crop species whose fibre, seeds, flowers and leaves are widely used by humans. The study of cannabinoids extracted from plants has been popular research topic in recent years. China is one of the origins of cannabis and one of the few countries with wild cannabis plants. However, the genetic structure of Chinese cannabis and the degree of adaptive selection remain unclear. RESULTS: The main morphological characteristics of wild cannabis in China were assessed. Based on whole-genome resequencing SNPs, Chinese cannabis could be divided into five groups in terms of geographical source and ecotype: wild accessions growing in the northwestern region; wild accessions growing in the northeastern region; cultivated accessions grown for fibre in the northeastern region; cultivated accessions grown for seed in northwestern region, and cultivated accessions in southwestern region. We further identified genes related to flowering time, seed germination, seed size, embryogenesis, growth, and stress responses selected during the process of cannabis domestication. The expression of flowering-related genes under long-day (LD) and short-day (SD) conditions showed that Chinese cultivated cannabis is adapted to different photoperiods through the regulation of Flowering locus T-like (FT-like) expression. CONCLUSION: This study clarifies the genetic structure of Chinese cannabis and offers valuable genomic resources for cannabis breeding.


Assuntos
Cannabis , Genoma de Planta , Cannabis/genética , Humanos , Fenótipo , Melhoramento Vegetal , Seleção Genética , Análise de Sequência de DNA
10.
Blood ; 135(25): 2302-2315, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32384137

RESUMO

Erythropoiesis is a complex multistage process that involves differentiation of early erythroid progenitors to enucleated mature red blood cells, in which lineage-specific transcription factors play essential roles. Erythroid Krüppel-like factor (EKLF/KLF1) is a pleiotropic erythroid transcription factor that is required for the proper maturation of the erythroid cells, whose expression and activation are tightly controlled in a temporal and differentiation stage-specific manner. Here, we uncover a novel role of G-protein pathway suppressor 2 (GPS2), a subunit of the nuclear receptor corepressor/silencing mediator of retinoic acid and thyroid hormone receptor corepressor complex, in erythrocyte differentiation. Our study demonstrates that knockdown of GPS2 significantly suppresses erythroid differentiation of human CD34+ cells cultured in vitro and xenotransplanted in nonobese diabetic/severe combined immunodeficiency/interleukin-2 receptor γ-chain null mice. Moreover, global deletion of GPS2 in mice causes impaired erythropoiesis in the fetal liver and leads to severe anemia. Flow cytometric analysis and Wright-Giemsa staining show a defective differentiation at late stages of erythropoiesis in Gps2-/- embryos. Mechanistically, GPS2 interacts with EKLF and prevents proteasome-mediated degradation of EKLF, thereby increasing EKLF stability and transcriptional activity. Moreover, we identify the amino acids 191-230 region in EKLF protein, responsible for GPS2 binding, that is highly conserved in mammals and essential for EKLF protein stability. Collectively, our study uncovers a previously unknown role of GPS2 as a posttranslational regulator that enhances the stability of EKLF protein and thereby promotes erythroid differentiation.


Assuntos
Eritropoese/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Fatores de Transcrição Kruppel-Like/fisiologia , Sequência de Aminoácidos , Animais , Células Cultivadas , Sequência Conservada , Células Precursoras Eritroides/citologia , Técnicas de Silenciamento de Genes , Transplante de Células-Tronco Hematopoéticas , Humanos , Subunidade gama Comum de Receptores de Interleucina/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/química , Fígado/embriologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Mapeamento de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Estabilidade Proteica , Proteólise , Interferência de RNA , RNA Interferente Pequeno/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Transplante Heterólogo , Ubiquitinação , Regulação para Cima
11.
Dermatol Ther ; 35(12): e15942, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36254686

RESUMO

We here report a case of a middle-aged man with an unusual case of bullous lichen sclerosus complicated with generalized morphea. He showed initial recurrent flaccid bullae, followed by ivory-white sclerotic plaques and extensive skin sclerosis, with additional walking disorder caused by knee-joint contracture, and ulcers on the lower extremities and back. The patient had no visceral involvement. After oral hydroxychloroquine and oral corticosteroids failed, the patient was given tofacitinib, which resolved his ulcers after 4 weeks and ameliorated his knee-joint contracture and skin sclerosis within 4 months. Owing to the occurrence of diffuse large B-cell lymphoma, he stopped using tofacitinib, and the ulcer and walking disorder reappeared. This is rare case of bullous lichen sclerosus-generalized morphea overlap syndrome. The patient recovered well after treatment with tofacitinib. His symptoms recurred after discontinuation of tofacitinib.


Assuntos
Contratura , Líquen Escleroso e Atrófico , Esclerodermia Localizada , Escleroderma Sistêmico , Dermatopatias , Pessoa de Meia-Idade , Masculino , Humanos , Esclerodermia Localizada/complicações , Esclerodermia Localizada/diagnóstico , Esclerodermia Localizada/tratamento farmacológico , Esclerose/complicações , Úlcera , Recidiva Local de Neoplasia
12.
Ear Hear ; 43(4): 1222-1227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35044995

RESUMO

OBJECTIVE: HIV positive (HIV+) individuals with otherwise normal hearing ability show central auditory processing deficits as evidenced by worse performance in speech-in-noise perception compared with HIV negative (HIV-) controls. HIV infection and treatment are also associated with lower neurocognitive screening test scores, suggesting underlying central nervous system damage. To determine how central auditory processing deficits in HIV+ individuals relate to brain alterations in the cortex involved with auditory processing, we compared auditory network (AN) functional connectivity between HIV+ adults with or without speech-in-noise perception difficulties and age-matched HIV- controls using resting-state fMRI. DESIGN: Based on the speech recognition threshold of the hearing-in-noise test, twenty-seven HIV+ individuals were divided into a group with speech-in-noise perception abnormalities (HIV+SPabnl, 38.2 ± 6.8 years; 11 males and 2 females) and one without (HIV+SPnl 34.4 ± 8.8 years; 14 males). An HIV- group with normal speech-in-noise perception (HIV-, 31.3 ± 5.2 years; 9 males and 3 females) was also enrolled. All of these younger and middle-aged adults had normal peripheral hearing determined by audiometry. Participants were studied using resting-state fMRI. Independent component analysis was applied to identify the AN. Group differences in the AN were identified using statistical parametric mapping. RESULTS: Both HIV+ groups had increased functional connectivity (FC) in parts of the AN including the superior temporal gyrus, middle temporal gyrus, supramarginal gyrus, and Rolandic operculum compared to the HIV- group. Compared with the HIV+SPnl group, the HIV+SPabnl group showed greater FC in parts of the AN including the middle frontal and inferior frontal gyri. CONCLUSIONS: The classical auditory areas in the temporal lobe are affected by HIV regardless of speech perception ability. Increased temporal FC in HIV+ individuals might reflect functional compensation to achieve normal primary auditory perception. Furthermore, increased frontal FC in the HIV+SPabnl group compared with the HIV+SPnl group suggest that speech-in-noise perception difficulties in HIV-infected adults also affect areas involved in higher-level cognition, providing imaging evidence consistent with the hypothesis that HIV-related neurocognitive deficits can include central auditory processing deficits.


Assuntos
Córtex Auditivo , Infecções por HIV , Percepção da Fala , Adulto , Audiometria , Limiar Auditivo/fisiologia , Feminino , Infecções por HIV/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Ruído , Percepção da Fala/fisiologia
13.
Biotechnol Appl Biochem ; 69(3): 1080-1093, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33928676

RESUMO

Many genes in the biosynthetic pathway of lipopolysaccharide in Cronobacter sakazakii have not been identified. In this study, we demonstrate that an operon containing four genes ESA_RS18945, ESA_RS18950, ESA_RS18955, and ESA_RS18960 is responsible for L-glycero-D-mannoheptose addition on the inner core of lipopolysaccharide in C. sakazakii. The proteins encoded by these four genes are homologous to E. coli WaaQ, WaaC, WaaF, and WaaD. Lipopolysaccharide from the deletion mutants of ESA_RS18945, ESA_RS18950, ESA_RS18955, and ESA_RS18960 (named as △RS18945, △RS18950, △RS18955 and △RS18960, respectively) were analyzed by SDS-PAGE. △RS18945 synthesized lipopolysaccharide with similar length to the wildtype BAA-894, whereas △RS18950, △RS18955, and △RS18960 synthesized much shorter lipopolysaccharide. This suggests that the enzyme encoded by ESA_RS18945 might function as E. coli WaaQ on the sidechain of lipopolysaccharide. When E. coli WaaC, WaaF, and WaaD were overexpressed in △RS18950, △RS18955, and △RS18960, respectively, the full length of lipopolysaccharide was recovered. Mass spectrometry analysis indicates that △RS18950 and △RS18960 only synthesized Kdo2 -lipid A, confirming that enzymes encoded by ESA_RS18950 and ESA_RS18960 have similar functions to E. coli WaaC and WaaD, respectively. Hep-Kdo2 -lipid A with a phosphoethanolamine was produced in △RS18955, suggesting that the enzyme encoded by ESA_RS18955 has similar function to E. coli WaaF.


Assuntos
Cronobacter sakazakii , Lipopolissacarídeos , Cronobacter sakazakii/genética , Cronobacter sakazakii/metabolismo , Escherichia coli/metabolismo , Glicosiltransferases/metabolismo , Lipídeo A/metabolismo , Lipopolissacarídeos/biossíntese , Lipopolissacarídeos/genética , Família Multigênica/genética
14.
BMC Biol ; 19(1): 137, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34225711

RESUMO

BACKGROUND: Lactose malabsorption occurs in around 68% of the world's population, causing lactose intolerance (LI) symptoms, such as abdominal pain, bloating, and diarrhea. To alleviate LI, previous studies have mainly focused on strengthening intestinal ß-galactosidase activity while neglecting the inconspicuous drop in the colon pH caused by the fermentation of non-hydrolyzed lactose by the gut microbes. A drop in colon pH will reduce the intestinal ß-galactosidase activity and influence intestinal homeostasis. RESULTS: Here, we synthesized a tri-stable-switch circuit equipped with high ß-galactosidase activity and pH rescue ability. This circuit can switch in functionality between the expression of ß-galactosidase and expression of L-lactate dehydrogenase in response to an intestinal lactose signal and intestinal pH signal, respectively. We confirmed that the circuit functionality was efficient in bacterial cultures at a range of pH levels, and in preventing a drop in pH and ß-galactosidase activity after lactose administration to mice. An impact of the circuit on gut microbiota composition was also indicated. CONCLUSIONS: Due to its ability to flexibly adapt to environmental variation, in particular to stabilize colon pH and maintain ß-galactosidase activity after lactose influx, the tri-stable-switch circuit can serve as a promising prototype for the relief of lactose intolerance.


Assuntos
Intolerância à Lactose , Animais , Fermentação , Microbioma Gastrointestinal , Lactose , Intolerância à Lactose/genética , Camundongos , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
15.
Antimicrob Agents Chemother ; 65(10): e0034121, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34310209

RESUMO

Gram-negative bacteria are intrinsically resistant to antibiotics due to the presence of the cell envelope, but the mechanisms of this resistance are still not fully understood. In this study, a series of mutants that lack one or more major components associated with the cell envelope were constructed from Escherichia coli K-12 W3110. WJW02 can only synthesize Kdo2-lipid A, which lacks the core oligosaccharide portion of lipopolysaccharide (LPS). WJW04, WJW07, and WJW08 were constructed from WJW02 by deleting the gene clusters relevant to the biosynthesis of exopolysaccharide, flagella, and fimbriae, respectively. WJW09, WJW010, and WJW011 cells cannot synthesize exopolysaccharide (EPS), flagella, and fimbria, respectively. Compared to the wild type (W3110), mutants WJW02, WJW04, WJW07, and WJW08 cells showed decreased resistance to more than 10 different antibacterial drugs, but the mutants WJW09, WJW010, and WJW011 did not. This indicates that the core oligosaccharide portion of lipopolysaccharide plays an important role in multiple antibiotic resistance in E. coli and that the first heptose in the core oligosaccharide portion is critical. Furthermore, the removal of the core oligosaccharide of LPS leads to influences on cell wall morphology, cell phenotypes, porins, efflux systems, and response behaviors to antibiotic stimulation. The results demonstrate the important role of lipopolysaccharide in the antibiotic resistance of Gram-negative bacteria.


Assuntos
Escherichia coli K12 , Escherichia coli , Resistência Microbiana a Medicamentos , Escherichia coli/genética , Escherichia coli K12/genética , Lipopolissacarídeos , Oligossacarídeos
16.
FASEB J ; 34(6): 8416-8427, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32350948

RESUMO

During human erythroid maturation, Hsp70 translocates into the nucleus and protects GATA-1 from caspase-3 cleavage. Failure of Hsp70 to localize to the nucleus was found in Myelodysplastic syndrome (MDS) erythroblasts and can induce dyserythropoiesis, with arrest of maturation and death of erythroblasts. However, the mechanism of the nuclear trafficking of Hsp70 in erythroblasts remains unknown. Here, we found the hematopoietic transcriptional regulator, EDAG, to be a novel binding partner of Hsp70 that forms a protein complex with Hsp70 and GATA-1 during human normal erythroid differentiation. EDAG overexpression blocked the cytoplasmic translocation of Hsp70 induced by EPO deprivation, inhibited GATA-1 degradation, thereby promoting erythroid maturation in an Hsp70-dependent manner. Furthermore, in myelodysplastic syndrome (MDS) patients with dyserythropoiesis, EDAG is dramatically down-regulated, and forced expression of EDAG has been found to restore the localization of Hsp70 in the nucleus and elevate the protein level of GATA-1 to a significant extent. In addition, EDAG rescued the dyserythropoiesis of MDS patients by increasing erythroid differentiation and decreasing cell apoptosis. This study demonstrates the molecular mechanism of Hsp70 nuclear sustaining during erythroid maturation and establishes that EDAG might be a suitable therapeutic target for dyserythropoiesis in MDS patients.


Assuntos
Núcleo Celular/metabolismo , Eritroblastos/metabolismo , Eritropoese/fisiologia , Proteínas de Choque Térmico HSP70/metabolismo , Síndromes Mielodisplásicas/metabolismo , Proteínas Nucleares/metabolismo , Apoptose/fisiologia , Caspase 3/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Citoplasma/metabolismo , Regulação da Expressão Gênica/fisiologia , Doenças Hematológicas/metabolismo , Humanos
17.
Anticancer Drugs ; 32(8): 829-841, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33929992

RESUMO

Circular RNAs (circRNAs) are revealed to regulate breast cancer progression. This study aimed to investigate hsa_circ_0069094-mediated effects on breast cancer cell malignancy. Quantitative real time PCR was employed to evaluate the expressions of hsa_circ_0069094, miR-661 and high mobility group A1 (HMGA1). Western blot was performed to determine the protein expression of HMGA1 and proliferating cell nuclear antigen. Breast cancer malignant progressions were explained by cell counting kit-8 proliferation, cell colony formation, flow cytometry analysis, wound-healing and transwell assays. Cell glycolysis was assessed by detecting glucose take, lactate production and hexokinase 2 (HK2) protein level. The target relationship between miR-661 and hsa_circ_0069094 or HMGA1 was predicted by circular RNA interactome and targetscan online databases, and identified by dual-luciferase reporter and RNA immunoprecipitation assay. The effects of hsa_circ_0069094 knockdown on breast cancer growth in vivo were elucidated by in vivo tumor formation assay. Hsa_circ_0069094 and HMGA1 expression were significantly upregulated, while miR-661 expression level was downregulated in breast cancer tissues and cells relative to adjacent normal breast tissues or MCF-10A cells. Functionally, hsa_circ_0069094 knockdown inhibited cell glycolysis, proliferation, migration and invasion, whereas induced cell apoptosis in breast cancer, which was decreased by miR-661 inhibitor. Mechanistically, hsa_circ_0069094 regulated HMGA1 by sponging miR-661. Furthermore, hsa_circ_0069094 knockdown repressed tumor formation in vivo. Collectively, hsa_circ_0069094 knockdown repressed breast cancer cell carcinogenesis and cell glycolysis by regulating HMGA1 through sponging miR-661, which provided a new insight for studying the mechanism of hsa_circ_0069094 in modulating breast cancer development.


Assuntos
Neoplasias da Mama/patologia , Proteína HMGA1a/metabolismo , MicroRNAs/metabolismo , RNA Circular/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos
18.
Am J Dermatopathol ; 43(1): e9-e12, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33337631

RESUMO

ABSTRACT: Rosai-Dorfman disease (RDD, also known as sinus histiocytosis with massive lymphadenopathy) is a rare and benign non-Langerhans cell histiocytosis. Skin biopsy usually shows nodular or diffuse dermatitis. Rosai-Dorfman cells (RDD cells) and emperipolesis are the key to diagnosis. RDD cells express S-100 antigen, CD68, CD163, α1-antitrypsin, α1-antichymotrypsin, and ham-56, whereas Langerhans cell markers such as CD1a and langerin are negative. We presented a case of a 55-year-old man with varying sizes of many dark red nodules and lumps over the face, trunk, and limbs for approximately 1 year but without systemic involvement. The results of the laboratory evaluations were notable for an increased level of serum IL-6 and serum IgG4. Histopathological examination showed a diffused dense nodular infiltration of "nude" epithelioid histiocytes with infiltration of minimal lymphocytes and plasm cells around the epithelioid nodules. Immunohistochemistry identified nodular histiocytes being stained strongly positive for S-100 and CD68 but negative for CD1a. Plasma cells showed focally positive for IgG, IgG4, and CD38 and with a ratio of IgG4/IgG >40%. Considering these findings, we believe that our case meets the diagnostic description of "cutaneous Rosai-Dorfman disease" and is, therefore, a rare case with clinical features of multiple tumor-like nodules, sarcoidosis-like histological features, and immunohistochemistry of IgG4-positive plasma cells.


Assuntos
Histiocitose Sinusal/patologia , Dermatopatias/patologia , Histiocitose Sinusal/imunologia , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Plasmócitos/imunologia , Dermatopatias/imunologia
19.
Carcinogenesis ; 41(5): 678-688, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31306481

RESUMO

Upregulation of histone methyltransferase SET domain bifurcated 1 (SETDB1) is associated with poor prognosis in cancer patients. However, the mechanism of oncogenicity of SETDB1 in cancer is hitherto unknown. Here, we show that SETDB1 is upregulated in human colorectal cancer (CRC) where its level correlates with poor clinical outcome. Ectopic SETDB1 promotes CRC cell proliferation, whereas SETDB1 attenuation inhibits this process. Flow cytometry reveals that SETDB1 promotes proliferation by driving the CRC cell cycle from G0/G1 phase to S phase. Mechanistically, SETDB1 binds directly to the STAT1 promoter region resulting in increased STAT1 expression. Functional characterization reveals that STAT1-CCND1/CDK6 axis is a downstream effector of SETDB1-mediated CRC cell proliferation. Furthermore, SETDB1 upregulation is sufficient to accelerate in vivo proliferation in xenograft animal model. Taken together, our results provide insight into the upregulation of SETDB1 within CRC and can lead to novel treatment strategies targeting this cell proliferation-promoting gene.


Assuntos
Biomarcadores Tumorais/metabolismo , Proliferação de Células , Neoplasias Colorretais/patologia , Ciclina D1/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Fator de Transcrição STAT1/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Movimento Celular , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Ciclina D1/genética , Quinase 6 Dependente de Ciclina/genética , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fator de Transcrição STAT1/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Biochem Biophys Res Commun ; 533(4): 1184-1190, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33041005

RESUMO

The nucleotide-binding domain and leucine-rich repeat-containing family pyrin domain containing 3 (NLRP3) inflammasome is involved in various acute and chronic liver diseases, however, it is not clear whether NLRP3 contributes to d-Galactosamine (D-GalN) plus lipopolysaccharide (LPS)-induced acute liver failure (ALF). This study aims to investigate the role of NLRP3 inflammasome in D-GalN/LPS-induced fatal hepatitis. We found that Nlrp3-/- and WT mice showed similar mortality against a lethal dose of D-GalN/LPS treatment. Serum ALT and AST levels, as well as liver necrosis area and hepatocyte apoptosis, were not significantly different between Nlrp3-/- and WT mice at 6 h after D-GalN/LPS injection. Moreover, the numbers of intrahepatic F4/80+ cells and Ly6G+ cells were comparable in two genotype mice following D-GalN/LPS treatment. Besides, Nlrp3-/- mice had reduced IL-1ß levels but similar TNF-α, IL-6, and MCP-1 levels compared with WT mice upon D-GalN/LPS administration. Our findings revealed that NLRP3 ablation does not protect mice from D-GalN/LPS-induced fatal hepatitis and has a marginal effect on intrahepatic inflammatory response upon D-GalN/LPS treatment. This suggests that NLRP3 inflammasome does not appear to be a major contributor to D-GalN/LPS-induced ALF.


Assuntos
Falência Hepática Aguda/etiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Galactosamina , Inflamassomos/metabolismo , Inflamassomos/fisiologia , Interleucina-1beta/sangue , Lipopolissacarídeos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/imunologia , Falência Hepática Aguda/metabolismo , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Necrose Tumoral alfa/sangue
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