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1.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34417297

RESUMEN

Two independent structures of the proton-pumping, respiratory cytochrome bo3 ubiquinol oxidase (cyt bo3 ) have been determined by cryogenic electron microscopy (cryo-EM) in styrene-maleic acid (SMA) copolymer nanodiscs and in membrane scaffold protein (MSP) nanodiscs to 2.55- and 2.19-Å resolution, respectively. The structures include the metal redox centers (heme b, heme o3 , and CuB), the redox-active cross-linked histidine-tyrosine cofactor, and the internal water molecules in the proton-conducting D channel. Each structure also contains one equivalent of ubiquinone-8 (UQ8) in the substrate binding site as well as several phospholipid molecules. The isoprene side chain of UQ8 is clamped within a hydrophobic groove in subunit I by transmembrane helix TM0, which is only present in quinol oxidases and not in the closely related cytochrome c oxidases. Both structures show carbonyl O1 of the UQ8 headgroup hydrogen bonded to D75I and R71I In both structures, residue H98I occupies two conformations. In conformation 1, H98I forms a hydrogen bond with carbonyl O4 of the UQ8 headgroup, but in conformation 2, the imidazole side chain of H98I has flipped to form a hydrogen bond with E14I at the N-terminal end of TM0. We propose that H98I dynamics facilitate proton transfer from ubiquinol to the periplasmic aqueous phase during oxidation of the substrate. Computational studies show that TM0 creates a channel, allowing access of water to the ubiquinol headgroup and to H98I.


Asunto(s)
Grupo Citocromo b/química , Grupo Citocromo b/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Hemo/metabolismo , Fosfolípidos/metabolismo , Bombas de Protones , Ubiquinona/metabolismo , Sitios de Unión , Microscopía por Crioelectrón , Hemo/química , Oxidación-Reducción , Conformación Proteica
2.
Int Microbiol ; 26(3): 579-589, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36705789

RESUMEN

Aspergillus oryzae HML366 is a newly screened cellulase-producing strain. The endoglucanase HML ED1 from A. oryzae HML366 was quickly purified by a two-step method that combines ammonium sulfate precipitation and strong anion exchange column. SDS-PAGE electrophoresis indicated that the molecular weight of the enzyme was 68 kDa. The optimum temperature of the purified endoglucanase was 60 ℃ and the enzyme activity was stable below 70 ℃. The optimum pH was 6.5, and the enzyme activity was stable at pH between 4.5 and 9.0. The analysis indicated that additional Na+, K+, Ca2+, and Zn2+ reduced the catalytic ability of enzyme to the substrate, but Mn2+ enhanced its catalytic ability to the substrate.The Km and Vmax of the purified endoglucanase were 8.75 mg/mL and 60.24 µmol/min·mg, respectively. In this study, we report for the first time that A. oryzae HML366 can produce a heat-resistant and wide pH tolerant endoglucanase HML ED1, which has potential industrial application value in bioethanol, paper, food, textile, detergent, and pharmaceutical industries.


Asunto(s)
Aspergillus oryzae , Celulasa , Aspergillus oryzae/metabolismo , Celulasa/metabolismo , Estabilidad de Enzimas , Temperatura , Calor , Concentración de Iones de Hidrógeno , Especificidad por Sustrato
3.
J Enzyme Inhib Med Chem ; 38(1): 398-404, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36476046

RESUMEN

The non-receptor protein tyrosine phosphatase (PTP) SHP2 encoded by the PTPN11 gene is a critical regulator in a number of cellular signalling processes and pathways, including the MAPK and the immune-inhibitory programmed cell death PD-L1/PD-1 pathway. Hyperactivation and inactivation of SHP2 is of great therapeutic interest for its association with multiple developmental disorders and cancer-related diseases. In this work, we characterised a potent SHP2 allosteric inhibitor 2-((3 R,4R)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-5-(2,3-dichlorophenyl)-3-methylpyrrolo[2,1-f][1,2,4]triazin-4(3H)-one (PB17-026-01) by using structure-based design. To study the structure-activity relationship, we compared co-crystal structures of SHP2 bound with PB17-026-01 and its analogue compound PB17-036-01, which is ∼20-fold less active than PB17-026-01, revealing that both of the compounds are bound to SHP2 in the allosteric binding pocket and PB17-026-01 forms more polar contacts with its terminal group. Overall, our results provide new insights into the modes of action of allosteric SHP2 inhibitor and a guide for the design of SHP2 allosteric inhibitor.


Asunto(s)
Triazinas , Triazinas/farmacología , Cristalografía por Rayos X , Proteína Tirosina Fosfatasa no Receptora Tipo 11
4.
J Gene Med ; 23(9): e3362, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33973298

RESUMEN

OBJECTIVE: The present study aimed to evaluate the efficacy of a non-invasive prenatal test (NIPT) in the detection of the sex chromosome aneuploidies (SCAs) at our prenatal diagnosis centre. METHODS: Among a cohort of 34,717 pregnancies, maternal plasma samples from our prenatal diagnosis centre were subject to analysis of SCAs using NIPT detection. Pregnant women with NIPT positive results of SCAs were recommended to undergo an invasive prenatal diagnosis (i.e. karyotyping and fluorescence in situ hybridization) to validate the prediction value of NIPT. RESULTS: From 34,717 clinical pregnancies, 229 (0.66%) pregnancies were identified with SCAs. Of these, 78 (34.1%) cases were positive for 45,X and 151 (65.9%) cases comprised a sex chromosome trisomy. Of the 229 positive NIPT results, 193 (84.3%) cases had accepted an invasive diagnosis involving karyotyping analysis of the amniotic fluid, which confirmed 67 cases (34.7%) as true positive, as well as 126 cases (65.3%) as false positive. The positive predictive values were 23.07%, 50%, 36% and 27.27% respectively. The remaining 36 (15.7%) cases declined a prenatal diagnosis. The termination rates of 45,X, 47,XXY, 47,XXX and 47,XYY were 20.5%,46%,12.9% and 11.5% respectively. CONCLUSIONS: NIPT demonstrated a lower accuracy in predicting monosomy X than sex chromosome trisomies. After invasive testing, the fetal chromosome with 45,X and 47,XXY were terminated more often than those with 47,XXX, 47,XYY. Because NIPT is a screening test, false positive/negative cases exist, and pre- and post-test counselling is essential for informing patients about the benefits and limitations of the test. Confirmatory testing of abnormal results is recommended prenatally or after birth, and the importance of confirmatory testing and benefits of early diagnosis should be addressed.


Asunto(s)
Aneuploidia , Pruebas Genéticas/métodos , Pruebas Prenatales no Invasivas/métodos , Diagnóstico Prenatal/métodos , Aberraciones Cromosómicas Sexuales , Trastornos de los Cromosomas Sexuales/diagnóstico , Adolescente , Adulto , China , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación/métodos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Trastornos de los Cromosomas Sexuales/genética , Adulto Joven
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(6): 603-608, 2020 Jun 10.
Artículo en Zh | MEDLINE | ID: mdl-32472533

RESUMEN

OBJECTIVE: To explore the cause for the failure of non-invasive prenatal testing (NIPT) and feasibility of repeated testing. METHODS: Clinical data, test results and pregnancy outcomes of 40 311 pregnant women who received NIPT test from January 2011 to December 2018 were reviewed. RESULTS: Among all the pregnant women, 1116 cases failed in the first test, 9 cases (0.81%) had fetal free DNA concentration lower than 4%, 663 cases (59.41%) were retested after the establishment of Z value gray area, and the remainder 444 cases (39.78%) needed to be retested after the blood collection due to the fetal free DNA concentration lower than 4%. After retesting, 1069 cases (95.78%) obtained effective NIPT results. The results showed that 53 cases were at high risk (6 cases for trisomy 21, 6 cases for trisomy 18, 13 cases for trisomy 13, 16 cases for sex chromosomal abnormality, 12 cases for chromosomal copy number variation). Forty-eight cases were selected for invasive prenatal diagnosis, and 2 cases of 47, XXY and 2 CNV were confirmed. A total of 47 cases (0.12%) did not obtain results because the concentration of fetal free DNA was lower than 4%. Only 16 cases (34%) chose invasive prenatal diagnosis. CONCLUSION: Repeated detection of the gray area of Z value can reduce the false positive rate of NIPT and invasive prenatal diagnosis, and the feasibility of repeated detection is high. In the case of fetal free DNA concentration lower than 4%, the success rate of obtaining effective NIPT results by re-sampling and re-detection increases with the increase of gestational age, but may delay the diagnosis for fetal aneuploidies. Therefore, personalized estimation should be made according to gestational age and clinical indications. It is suggested that pregnant women should choose invasive prenatal diagnosis when they have failed in the retest.


Asunto(s)
Diagnóstico Prenatal , Aneuploidia , Trastornos de los Cromosomas , Variaciones en el Número de Copia de ADN , Estudios de Factibilidad , Femenino , Humanos , Masculino , Embarazo , Trisomía
6.
Cell Physiol Biochem ; 51(1): 315-336, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30453281

RESUMEN

BACKGROUND/AIMS: Gap junctions, which are assembled by connexins, can directly connect the cytoplasm of adjacent cells and enable gap junctional intercellular communication (GJIC) as well as metabolic coupling between neighboring cells. Here, we investigated the role of connexin 43 (Cx43) and its derived GJIC in the interplay between non-small cell lung cancer (NSCLC) cells and cancer-associated fibroblasts (CAFs). METHODS: CAFs and NSCLC cells were co-cultured with direct contact and separated using flow cytometry. Glucose uptake, lactate production, and the expression and activity of PKM-2 and LDH-A in sorted CAFs were measured by a colorimetric assay, western blotting, and enzyme-linked immunosorbent assay (ELISA). Meanwhile, E-cadherin and N-cadherin expression and the migration and invasion of sorted NSCLC cells were detected by western blotting, wound width, and Transwell assays. Pyruvate, acetyl-CoA, and citric acid levels, ATP levels, and LDH-B and α-KG activity in sorted NSCLC cells were determined by a colorimetric or fluorometric assay and ELISA, respectively. Functional GJIC between cells and the subcellular location of connexins were detected by a "Parachute" assay and immunofluorescence. Levels of α-SMA, Cx43, and LDH-B in tissue from patients with NSCLC were determined by immunohistochemistry. RESULTS: Cx43 accumulated in the plasma membrane, which favored the assembly of asymmetric unidirectional GJIC from CAFs to NSCLC cells. CAFs underwent increased aerobic glycolysis and promoted the epithelial-mesenchymal transition, migration, and invasion of NSCLC cells. In contrast, NSCLC cells experienced enhanced oxidative phosphorylation upon CAF stimulation, with an increase in ATP generation and thereby activation of the PI3K/Akt and MAPK/ERK pathways. Metabolic coupling between CAFs and NSCLC cells was under the strict control of Cx43-formed unidirectional GJIC. Patients with high tri-expression of α-SMA, Cx43, and LDH-B had the shortest overall survival and relapse-free survival compared with those with individual overexpression or high bi-expression. CONCLUSION: Cx43-formed unidirectional GJIC plays a critical role in mediating close metabolic cooperation between CAFs and NSCLC cells to support the malignant progression of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Conexina 43/metabolismo , Uniones Comunicantes/metabolismo , Neoplasias Pulmonares/patología , Adenosina Trifosfato/metabolismo , Cadherinas/metabolismo , Fibroblastos Asociados al Cáncer/citología , Fibroblastos Asociados al Cáncer/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Línea Celular Tumoral , Movimiento Celular , Conexina 43/antagonistas & inhibidores , Conexina 43/genética , Transición Epitelial-Mesenquimal , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Transducción de Señal
7.
J Sep Sci ; 38(3): 460-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25431240

RESUMEN

A new method was developed for the simultaneous determination of three catecholamines in urine using aminophenylboronic acid functionalized magnetic nanoparticles extraction followed by high-performance liquid chromatography with electrochemical detection. Novel aminophenylboronic acid functionalized magnetic nanoparticles were prepared by multi-step covalent modification, and characterized by transmission electron microscopy, Fourier-transformed infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometry. With the help of the high affinity between the boronate and cis-diol group, the particles were used for the highly selective separation and enrichment of three major catecholamines, norepinephrine, epinephrine, and dopamine. Effects of the pH of the feed solution, the extraction time, the composition of the buffer solution, the amount of the magnetic particles, the elution conditions, and the recycling of aminophenylboronic acid functionalized magnetic nanoparticles were explored. Under the optimized conditions, 13-17-fold enrichment factors were obtained. The linear ranges were 0.01-2.0 µg/mL for the studied analytes. The limits of detection and quantification were in the range of 2.0-7.9 and 6.7-26.3 ng/mL, respectively. The relative recoveries were in the range of 92-108%, with intraday and interday relative standard deviations lower than 6.8%. This method was successfully applied to analysis of catecholamines in real urine.


Asunto(s)
Ácidos Borónicos/química , Catecolaminas/orina , Técnicas Electroquímicas , Nanopartículas de Magnetita/química , Adulto , Cromatografía Líquida de Alta Presión , Femenino , Voluntarios Sanos , Humanos , Masculino , Adulto Joven
8.
Zhonghua Zhong Liu Za Zhi ; 37(12): 890-8, 2015 Dec.
Artículo en Zh | MEDLINE | ID: mdl-26887616

RESUMEN

OBJECTIVE: To investigate the antitumor efficacy and mechanism of HSP90 inhibitor FW-04-806 against Bcr/Abl(+) leukemia K562 and HL60 cells and their mechanisms of action. METHODS: MTT assay was used to assess the proliferation-inhibiting effect of FW-04-806. Cell cycle was analyzed with propidium iodide by flow cytometry. Cell apoptosis was determined using the FITC mV apoptosis detection kit. Western blot was applied to reveal the protein expression of related proliferative and apoptotic signaling pathways. The changes of mitochondrial membrane potential were detected by flow cytometry. Protein-protein interactions was shown by co-immunoprecipitation. The level of mRNA was assessed by real-time RT-PCR. RESULTS: FW-04-806 obviously inhibited cell proliferation in the HL60, K562 and HL60/Bcr-Abl cell lines, with an IC50 of (30.89 ± 0.12) µmol/L, (9.76 ± 0.19) µmol/L and (8.03 ± 0.26) µmol/L, respectively (P<0.001). Compared with the vehicle group, the two increasing doses of FW-04-806 showed inhibition of tumor growth at a rate of (17.40 ± 0.34)% and (34.33 ± 5.00)%, respectively, in the K562 cell line groups (P=0.003), and (18.90 ± 1.45)% and (35.60 ± 3.55)% (P=0.001) in the HL60/Bcr-Abl cell line groups. FW-04-806 dissociated Hsp90/Cdc37 chaperon/co-chaperon complex, followed by degradation of the Hsp90 proteins through proteasome pathway without affecting mRNA expression. FW-04-806 induced apoptosis and led to G2/M arrest. CONCLUSION: Our findings indicate that FW-04-806 displays potential antitumor effect by suppressing the proliferation and apoptosis in Bcr/Abl(+) leukemia cells in vivo.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteínas de Fusión bcr-abl , Leucemia/tratamiento farmacológico , Ciclo Celular , Células HL-60 , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Células K562 , Leucemia/metabolismo , Leucemia/patología , Potencial de la Membrana Mitocondrial , Oxazoles/farmacología , ARN Mensajero/metabolismo , Transducción de Señal
9.
Clin Case Rep ; 12(4): e8590, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38560284

RESUMEN

Bladder duplication and congenital bladder diverticulum are rare anomalies. We described two boys with rare bladder anomalies found on prenatal ultrasounds. Postnatal investigations and surgical findings confirmed these bladder anomalies. The malformation was associated with other system anomalies. This report of pre- and postnatal imaging with surgical correlation contributes to our understanding about these rare bladder anomalies.

10.
Med Image Anal ; 91: 102983, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37926035

RESUMEN

Positron emission tomography (PET) scans can reveal abnormal metabolic activities of cells and provide favorable information for clinical patient diagnosis. Generally, standard-dose PET (SPET) images contain more diagnostic information than low-dose PET (LPET) images but higher-dose scans can also bring higher potential radiation risks. To reduce the radiation risk while acquiring high-quality PET images, in this paper, we propose a 3D multi-modality edge-aware Transformer-GAN for high-quality SPET reconstruction using the corresponding LPET images and T1 acquisitions from magnetic resonance imaging (T1-MRI). Specifically, to fully excavate the metabolic distributions in LPET and anatomical structural information in T1-MRI, we first use two separate CNN-based encoders to extract local spatial features from the two modalities, respectively, and design a multimodal feature integration module to effectively integrate the two kinds of features given the diverse contributions of features at different locations. Then, as CNNs can describe local spatial information well but have difficulty in modeling long-range dependencies in images, we further apply a Transformer-based encoder to extract global semantic information in the input images and use a CNN decoder to transform the encoded features into SPET images. Finally, a patch-based discriminator is applied to ensure the similarity of patch-wise data distribution between the reconstructed and real images. Considering the importance of edge information in anatomical structures for clinical disease diagnosis, besides voxel-level estimation error and adversarial loss, we also introduce an edge-aware loss to retain more edge detail information in the reconstructed SPET images. Experiments on the phantom dataset and clinical dataset validate that our proposed method can effectively reconstruct high-quality SPET images and outperform current state-of-the-art methods in terms of qualitative and quantitative metrics.


Asunto(s)
Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Humanos , Tomografía de Emisión de Positrones/métodos , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen , Benchmarking , Procesamiento de Imagen Asistido por Computador/métodos
11.
Ther Clin Risk Manag ; 19: 801-810, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37850071

RESUMEN

Purpose: To compare and analyze the therapeutic effects of endoscopy-assisted laparoscopic surgery (EALS) and laparoscopic surgery (LS) in the treatment of gastric duplication cysts (GDCs). Patients and Methods: We reviewed the clinical data of children with GDCs who underwent surgical treatment at Hubei Maternal and Child Health Hospital, Yijishan Hospital of Wannan Medical College, and Qingdao Women and Children's Medical Center from September 2014 to November 2022. Results: The study comprised 29 children with GDCs, including 14 in the EALS group and 15 in the LS group. There was no significant difference between the two groups in terms of age, sex, weight, and cyst size characteristics. There was a significant difference between the two groups in terms of average surgical time (P>0.05), which was 1.100 ± 0.833 hours in the EALS group and 1.933 ± 0.159 hours in the LS group. There was a significant difference between the two groups (P<0.05) in average intraoperative blood loss, which was 7.93 ± 3.81 milliliters in the EALS group and 11.80 ± 2.72 milliliters in the LS group. There was a significant difference between the two groups (P<0.05) in average postoperative fasting time, which was 73.79 ± 8.36 hours in the EALS group and 114.1 ± 9.24 hours in the LS group. There was a significant difference between the two groups (P<0.05) in average postoperative hospital stay, which was 10.21 ± 4.25 days in the EALS group and 14.47 ± 4.36 days in the LS group. Conclusion: EALS technology can not only shorten surgical time, accurately locate GDCs, reduce injuries, and decrease the probability of complications but also achieve treatment goals safely and reliably.

12.
Expert Rev Mol Diagn ; 23(7): 635-642, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37249149

RESUMEN

OBJECTIVE: To evaluate whether the fetal fraction of cell-free DNA at the first and second trimesters is associated with spontaneous preterm birth. METHODS: This was a retrospective cohort study with singleton pregnancies who underwent noninvasive prenatal testing. According to pregnancy outcome, eligible patients were divided into a delivery group ≥37 weeks of pregnancy (term group) and <37 weeks of pregnancy (spontaneous preterm group). Stepwise linear regression was used to identify maternal characteristics associated with the fetal fraction of cell-free DNA. Logistic regression analysis was performed to evaluate the association between the fetal fraction of cell-free DNA and spontaneous preterm birth, adjusted for confounding factors. RESULTS: 14,020 cases were included in the study, 13292 cases (94.81%) in the term group and 728 cases (5.19%) in the spontaneous preterm group. The cell-free fraction of fetal DNA was inversely correlated with maternal age and body mass index. Positively correlated with gestational age, fertility, and assisted reproductive technology. After adjusting for the covariates, logistic regression analysis revealed no statistically significant association between the fetal fraction of cell-free DNA and spontaneous preterm birth. CONCLUSION: In our original study, we found no association between the fetal fraction on NIPT and subsequent spontaneous preterm birth.


Asunto(s)
Ácidos Nucleicos Libres de Células , Nacimiento Prematuro , Femenino , Embarazo , Humanos , Recién Nacido , Nacimiento Prematuro/diagnóstico , Nacimiento Prematuro/etiología , Segundo Trimestre del Embarazo , Estudios Retrospectivos , Edad Gestacional
13.
Expert Rev Mol Diagn ; : 1-6, 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36939534

RESUMEN

OBJECTIVES: To evaluate the clinical efficiency of noninvasive prenatal testing (NIPT) for fetal chromosomal aneuploidy screening in twin pregnancies. METHODS: A total of 1650 women with twin pregnancies were enrolled in the study, which underwent NIPT at the Southwest Hospital, Army Medical University, Chongqing, China from January 2013 to June 2022. Fetal karyotyping analysis was conducted in high-risk patients, with subsequent follow-up on pregnancy outcomes. RESULTS: In 1650 pregnancies, NIPT results showed ten cases of the fetal chromosome aneuploidy, of which six cases were true positive and four cases were false positive. The sensitivity, specificity, positive predictive value (PPV), and false-positive rate (FPR) of trisomy 21 were 100%, 99.79%, 57.14%, and 0.18%, respectively. Sensitivity, specificity, PPV, and FPR of trisomy 18 were 100%, 99.94%, 50%, and 0.06%, respectively. The sensitivity, specificity, PPV, and FPR of trisomy 13 were 100%, 100%, 100%, and 0%, respectively. No false negatives were detected and the negative predictive value (NPV) was 100% of the total. Eleven pregnancies failed the NIPT test with no-call due to the low fetal fraction (< 4%). CONCLUSIONS: NIPT is a high-performing routine primary prenatal screening test in twin pregnancies, with high sensitivity and specificity in screening for fetal aneuploidy.

14.
Front Oncol ; 12: 884369, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35692794

RESUMEN

The incidence of hepatocellular carcinoma (HCC) is increasing worldwide. Extracellular vesicles (EVs) contain sufficient bioactive substances and are carriers of intercellular information exchange, as well as delivery vehicles for nucleic acids, proteins and drugs. Although EVs show great potential for the treatment of HCC and their role in HCC progression has been extensively studied, there are still many challenges such as time-consuming extraction, difficult storage, easy contamination, and low drug loading rate. We focus on the biogenesis, morphological characteristics, isolation and extraction of EVs and their significance in the progression of HCC, tumor invasion, immune escape and cancer therapy for a review. EVs may be effective biomarkers for molecular diagnosis of HCC and new targets for tumor-targeted therapy.

15.
Med Image Anal ; 77: 102335, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34979432

RESUMEN

Positron emission tomography (PET) is a typical nuclear imaging technique, which can provide crucial functional information for early brain disease diagnosis. Generally, clinically acceptable PET images are obtained by injecting a standard-dose radioactive tracer into human body, while on the other hand the cumulative radiation exposure inevitably raises concerns about potential health risks. However, reducing the tracer dose will increase the noise and artifacts of the reconstructed PET image. For the purpose of acquiring high-quality PET images while reducing radiation exposure, in this paper, we innovatively present an adaptive rectification based generative adversarial network with spectrum constraint, named AR-GAN, which uses low-dose PET (LPET) image to synthesize standard-dose PET (SPET) image of high-quality. Specifically, considering the existing differences between the synthesized SPET image by traditional GAN and the real SPET image, an adaptive rectification network (AR-Net) is devised to estimate the residual between the preliminarily predicted image and the real SPET image, based on the hypothesis that a more realistic rectified image can be obtained by incorporating both the residual and the preliminarily predicted PET image. Moreover, to address the issue of high-frequency distortions in the output image, we employ a spectral regularization term in the training optimization objective to constrain the consistency of the synthesized image and the real image in the frequency domain, which further preserves the high-frequency detailed information and improves synthesis performance. Validations on both the phantom dataset and the clinical dataset show that the proposed AR-GAN can estimate SPET images from LPET images effectively and outperform other state-of-the-art image synthesis approaches.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Tomografía de Emisión de Positrones , Artefactos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Tomografía de Emisión de Positrones/métodos
16.
Nat Commun ; 13(1): 6422, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36307425

RESUMEN

Cytochromes c use heme as a cofactor to carry electrons in respiration and photosynthesis. The cytochrome c maturation system I, consisting of eight membrane proteins (CcmABCDEFGH), results in the attachment of heme to cysteine residues of cytochrome c proteins. Since all c-type cytochromes are periplasmic, heme is first transported to a periplasmic heme chaperone, CcmE. A large membrane complex, CcmABCD has been proposed to carry out this transport and linkage to CcmE, yet the structural basis and mechanisms underlying the process are unknown. We describe high resolution cryo-EM structures of CcmABCD in an unbound form, in complex with inhibitor AMP-PNP, and in complex with ATP and heme. We locate the ATP-binding site in CcmA and the heme-binding site in CcmC. Based on our structures combined with functional studies, we propose a hypothetic model of heme trafficking, heme transfer to CcmE, and ATP-dependent release of holoCcmE from CcmABCD. CcmABCD represents an ABC transporter complex using the energy of ATP hydrolysis for the transfer of heme from one binding partner (CcmC) to another (CcmE).


Asunto(s)
Proteínas de Escherichia coli , Hemoproteínas , Hemo/metabolismo , Proteínas de Escherichia coli/metabolismo , Hemoproteínas/química , Proteínas de la Membrana Bacteriana Externa/metabolismo , Citocromos c/metabolismo , Escherichia coli/metabolismo , Proteínas Bacterianas/metabolismo , Adenosina Trifosfato/metabolismo
17.
Yi Chuan ; 33(6): 607-12, 2011 Jun.
Artículo en Zh | MEDLINE | ID: mdl-21684866

RESUMEN

To study the relationship between the concentrations of INH B (Inhibin B), ACT A (Activin A), and FSH (Follicle stimulating hormone) in blood plasma and fecundity, Dazu black goat with high productivity and Sannen dairy goat with low productivity were used as experiment objects in this research. The concentrations of INH B, ACT A, and FSH in blood plasma were measured by enzyme-linked immunosorbent assay (ELISA) in order to study the secretion rule of INH B, ACT A, and FSH during an estrus cycle of two goat breeds. The results indicated that the secretion of FSH showed a positive correlation with ACT A and a negative correlation with INH B. The mean concentration of FSH in Dazu black goat was higher than that in Sanen dairy goat during a estrous cycle. However, during the time from obviously estrus to ovulation, the mean concentration of FSH in Dazu black goat was significantly higher than that in Sannen dairy goat (0.01

Asunto(s)
Activinas/sangre , Industria Lechera , Ciclo Estral/sangre , Hormona Folículo Estimulante/sangre , Cabras/sangre , Cabras/fisiología , Inhibinas/sangre , Activinas/metabolismo , Animales , Ciclo Estral/metabolismo , Femenino , Hormona Folículo Estimulante/metabolismo , Cabras/metabolismo , Inhibinas/metabolismo
18.
Front Genet ; 12: 731815, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34992628

RESUMEN

Background: Chromosomal aberrations contribute to human phenotypic diversity and disease susceptibility, but it is difficult to assess their pathogenic effects in the clinic. Therefore, it is of great value to report new cases of chromosomal aberrations associated with normal phenotypes or clinical abnormalities. Methods: This was a retrospective analysis of seven pedigrees that carried 21q21.1-q21.2 aberrations. G-banding and single-nucleotide polymorphism array techniques were used to analyze chromosomal karyotypes and copy number variations in the fetuses and their family members. Results: All fetuses and their family members showed normal karyotypes in seven pedigrees. Here, it was revealed that six fetuses carried maternally inherited 21q21.1-q21.2 duplications, ranging from 1 to 2.7 Mb, but none of the mothers had an abnormal phenotype. In one fetus, an 8.7 Mb deletion of 21q21.1-q21.2 was found. An analysis of the pedigree showed that the deletion was also observed in the mother, brother, and maternal grandmother, but no abnormal phenotypes were found. Conclusion: This study identified 21q21.1-q21.2 aberrations in Chinese pedigrees. The carriers of 21q21.1-q21.2 duplications had no clinical consequences based on their phenotypes, and the 21q21.1-q21.2 deletion was transmitted through three generations of normal individuals. This provides benign clinical evidence for pathogenic assessment of 21q21.1-q21.2 duplication and deletion, which was considered a variant of uncertain significance and a likely pathogenic variant in previous reports.

19.
Eur J Med Genet ; 63(9): 104001, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32622960

RESUMEN

OBJECTIVE: To evaluate the efficacy of non-invasive prenatal test (NIPT) in the detection of chromosomal aneuploidy according to the follow-up information from a single prenatal diagnosis center. METHODS: A total of 40,311 cases were retrospectively reviewed. The screening was performed using a BGI protocol, pre-test and post-test genetic counseling was provided, and the pregnancy outcomes were recorded. The results of NIPT and clinical follow-up data were analyzed together with the pregnancy outcomes, confirmatory testing results, and ultrasound findings. RESULTS: Of the 40,311cases were includes in the study, successful follow-up was conducted in 468 (1.16%) cases with high risk, 225 (0.56%) cases with rare autosomal trisomy (RAT) and copy number variation (CNV). 39,572 (98.17%) cases with low risk and 623 (1.57%) cases of which were confirmed with adverse pregnancy outcomes. 46 (0.1%) cases with failed tests. Among them, 398 (84.7%) cases with high-risk results chose invasive testing, revealing 198 true positive cases. In cases with RAT and CNV results, 189 cases underwent invasive testing, revealing 5 cases RAT and 4 pathogenic CNVs. CONCLUSIONS: NIPT appears to be effective in detecting the fetal chromosomal aneuploidies T21, T18 and SCAs, but it exist false positive/negative cases, unconfirmed high-risk cfDNA results, and the high false positive rate in cases with RAT and CNV results implied the limitations of this screening method. Our study showed the importance to associate cfDNA screening results with clinical follow-up data and provided information that may help with result interpretation, genetic counseling and the decision making in clinic.


Asunto(s)
Aneuploidia , Trastornos de los Cromosomas/diagnóstico , Pruebas Prenatales no Invasivas/normas , Adulto , Trastornos de los Cromosomas/genética , Toma de Decisiones Clínicas , Variaciones en el Número de Copia de ADN , Femenino , Asesoramiento Genético , Humanos , Persona de Mediana Edad , Pruebas Prenatales no Invasivas/métodos , Pruebas Prenatales no Invasivas/estadística & datos numéricos , Embarazo , Resultado del Embarazo
20.
Pharmacogenomics ; 20(3): 143-153, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30808275

RESUMEN

AIM: The aim of this study was to investigate the role of long noncoding RNAs (lncRNAs) profiles in cancer-associated fibroblasts (CAFs) during non-small-cell lung cancer (NSCLC) progression. MATERIALS & METHODS: Differentially expressed lncRNAs and mRNAs were detected by lncRNA microarray between three patient-paired CAFs and the adjacent normal fibroblasts, which were obtained from tumoral and nontumoral portions of surgically resected lung tissue from three primary NSCLCs. Bioinformatic analyses including gene ontology and pathway analysis were applied to these differentially expressed mRNAs. The qRT-PCR was conducted to identify the change of selected lncRNAs that might be involved in contribution of CAFs toward NSCLC. RESULTS: A total of 766 lncRNAs and 750 mRNAs abnormally expressed in CAFs (fold-change >2, p < 0.05). Bioinformatic analyses indicated that these mRNAs are associated with immune function. The qPCR results were consistent with microarray data. CONCLUSION: The lncRNAs profiles of CAFs may provide promising targets for further research on immune regulation during NSCLC process.


Asunto(s)
Fibroblastos Asociados al Cáncer/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Perfilación de la Expresión Génica/métodos , ARN Largo no Codificante/genética , Fibroblastos Asociados al Cáncer/patología , Carcinoma de Pulmón de Células no Pequeñas/patología , Biología Computacional , Regulación Neoplásica de la Expresión Génica/genética , Ontología de Genes , Redes Reguladoras de Genes/genética , Humanos , Cultivo Primario de Células , ARN Largo no Codificante/clasificación , ARN Mensajero/genética , Transducción de Señal/genética
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