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1.
Nucleic Acids Res ; 50(12): e69, 2022 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-35325178

RESUMEN

The nucleolus is a subnuclear membraneless compartment intimately involved in ribosomal RNA synthesis, ribosome biogenesis and stress response. Multiple optogenetic devices have been developed to manipulate nuclear protein import and export, but molecular tools tailored for remote control over selective targeting or partitioning of cargo proteins into subnuclear compartments capable of phase separation are still limited. Here, we report a set of single-component photoinducible nucleolus-targeting tools, designated pNUTs, to enable rapid and reversible nucleoplasm-to-nucleolus shuttling, with the half-lives ranging from milliseconds to minutes. pNUTs allow both global protein infiltration into nucleoli and local delivery of cargoes into the outermost layer of the nucleolus, the granular component. When coupled with the amyotrophic lateral sclerosis (ALS)-associated C9ORF72 proline/arginine-rich dipeptide repeats, pNUTs allow us to photomanipulate poly-proline-arginine nucleolar localization, perturb nucleolar protein nucleophosmin 1 and suppress nascent protein synthesis. pNUTs thus expand the optogenetic toolbox by permitting light-controllable interrogation of nucleolar functions and precise induction of ALS-associated toxicity in cellular models.


Asunto(s)
Esclerosis Amiotrófica Lateral , Nucléolo Celular , Optogenética/métodos , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/metabolismo , Proteína C9orf72/química , Nucléolo Celular/metabolismo , Sistemas de Liberación de Medicamentos , Humanos , Proteínas Nucleares/metabolismo , Inhibidores de la Síntesis de la Proteína/administración & dosificación
2.
BMC Anesthesiol ; 24(1): 12, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172695

RESUMEN

BACKGROUND: The alteration of the prognostic nutritional index (PNI) or the utilization of distinct anesthesia strategies has been linked to the prognosis of various cancer types, but the existing evidence is limited and inconclusive, particularly for colorectal cancer (CRC). Our objective was to evaluate the association between PNI change and progression free survival (PFS) and overall survival (OS) in patients treated with CRC surgery after propofol-based or sevoflurane-based anesthesia. METHODS: We conducted a retrospective analysis of 414 patients with CRC who underwent surgical resection. Among them, 165 patients received propofol-based total intravenous anesthesia (TIVA-P), while 249 patients received sevoflurane-based inhalation anesthesia (IA-S). The PNI change (ΔPNI) was calculated by subtracting the pre-surgery PNI from the post-surgery PNI, and patients were categorized into high (≥ -2.25) and low (< -2.25) ΔPNI groups. Univariate and multivariate analyses were employed to evaluate the effects of the two anesthesia methods, ΔPNI, and their potential interaction on PFS and OS. RESULTS: The median duration of follow-up was 35.9 months (interquartile range: 18-60 months). The five-year OS rates were 63.0% in the TIVA-P group and 59.8% in the IA-S group (hazard ratio [HR]: 0.96; 95% confidence interval [CI]: 0.70-1.35; p = 0.864), while the five-year PFS rates were 55.8% and 51.0% (HR: 0.92; 95% CI: 0.68-1.26; p = 0.614), respectively. In comparison to patients in the low ΔPNI group, those in the high ΔPNI group exhibited a favorable association with both OS (HR: 0.57; 95% CI: 0.40-0.76; p < 0.001) and PFS (HR: 0.58; 95% CI: 0.43-0.79; p < 0.001). Stratified analysis based on ΔPNI revealed significant protective effects in the propofol-treated participants within the high ΔPNI group, whereas such effects were not observed in the low ΔPNI group, for both OS (p for interaction = 0.004) and PFS (p for interaction = 0.024). CONCLUSIONS: Our data revealed that among patients who underwent CRC surgery, those treated with TIVA-P exhibited superior survival outcomes compared to those who received IA-S, particularly among individuals with a high degree of PNI change.


Asunto(s)
Neoplasias Colorrectales , Propofol , Humanos , Pronóstico , Sevoflurano , Evaluación Nutricional , Estudios Retrospectivos , Resultado del Tratamiento , Anestesia por Inhalación/métodos , Neoplasias Colorrectales/cirugía
3.
HIV Med ; 24(7): 777-784, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36843437

RESUMEN

OBJECTIVES: Our objective was to assess the HIV-1 quantification performance of the Livzon HIV-1 viral load (VL) assay and the Roche Cobas HIV-1 assay to evaluate an HIV-1 VL testing reagent for application in China. METHOD: We compared the Livzon and Roche Cobas HIV-1 VL assays using ethylenediaminetetraacetic acid plasma samples collected between May 2021 and November 2021 from patients with HIV-1 and healthy controls. We used Cohen's κ coefficient to measure agreement of qualitative values and Pearson's correlation coefficient (r) values and the coefficient of determination (R2 ) to determine the linear relationship between the two assays. We performed a Bland-Altman analysis to assess VL quantification agreement. RESULTS: In total, 11 plasma samples from patients with hepatitis B virus (HBV) or hepatitis C virus (HCV) and nine samples from healthy controls were undetectable on both assays. Overall agreement was seen in 419 of 500 specimens (91.40%), with a κ value of 0.59. Pearson's correlation coefficient between the two assays was 0.970. Using the Bland-Altman method, 95.14% (352/370) of paired VLs fell within the 95% confidence limits of agreement (-0.51 to 0.95 log10  copies/mL). Higher VLs had a better correlation and a smaller mean difference between the two assays. Pearson's correlation coefficient for the samples of subtype CRF01_AE, CRF07_BC, and CRF55_01B was 0.950, 0.935, and 0.952, respectively. CONCLUSION: The Livzon HIV-1 VL assay exhibits good precision and linearity and a high correlation with the Roche Cobas HIV-1 assay. The Livzon HIV-1 VL assay has salient advantages in terms of the lyophilized powder reagent, which gives the assay greater stability and sensitivity and can be readily used in low-resource areas.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Humanos , VIH-1/genética , Carga Viral , Infecciones por VIH/diagnóstico , ARN Viral , Sensibilidad y Especificidad
4.
Blood ; 137(25): 3548-3562, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-33690842

RESUMEN

The tight regulation of intracellular nucleotides is critical for the self-renewal and lineage specification of hematopoietic stem cells (HSCs). Nucleosides are major metabolite precursors for nucleotide biosynthesis and their availability in HSCs is dependent on their transport through specific membrane transporters. However, the role of nucleoside transporters in the differentiation of HSCs to the erythroid lineage and in red cell biology remains to be fully defined. Here, we show that the absence of the equilibrative nucleoside transporter (ENT1) in human red blood cells with a rare Augustine-null blood type is associated with macrocytosis, anisopoikilocytosis, an abnormal nucleotide metabolome, and deregulated protein phosphorylation. A specific role for ENT1 in human erythropoiesis was demonstrated by a defective erythropoiesis of human CD34+ progenitors following short hairpin RNA-mediated knockdown of ENT1. Furthermore, genetic deletion of ENT1 in mice was associated with reduced erythroid progenitors in the bone marrow, anemia, and macrocytosis. Mechanistically, we found that ENT1-mediated adenosine transport is critical for cyclic adenosine monophosphate homeostasis and the regulation of erythroid transcription factors. Notably, genetic investigation of 2 ENT1null individuals demonstrated a compensation by a loss-of-function variant in the ABCC4 cyclic nucleotide exporter. Indeed, pharmacological inhibition of ABCC4 in Ent1-/- mice rescued erythropoiesis. Overall, our results highlight the importance of ENT1-mediated nucleotide metabolism in erythropoiesis.


Asunto(s)
Adenosina Monofosfato/metabolismo , Tranportador Equilibrativo 1 de Nucleósido/metabolismo , Eritropoyesis , Células Madre Hematopoyéticas/metabolismo , Homeostasis , Animales , Tranportador Equilibrativo 1 de Nucleósido/genética , Humanos , Ratones , Ratones Noqueados
5.
PLoS Genet ; 16(12): e1009286, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33370779

RESUMEN

Developmental-regulatory networks often include large gene families encoding mechanistically-related proteins like G-protein-coupled receptors, zinc finger transcription factors and solute carrier (SLC) transporters. In principle, a common mechanism may confer expression of multiple members integral to a developmental process, or diverse mechanisms may be deployed. Using genetic complementation and enhancer-mutant systems, we analyzed the 456 member SLC family that establishes the small molecule constitution of cells. This analysis identified SLC gene cohorts regulated by GATA1 and/or GATA2 during erythroid differentiation. As >50 SLC genes shared GATA factor regulation, a common mechanism established multiple members of this family. These genes included Slc29a1 encoding an equilibrative nucleoside transporter (Slc29a1/ENT1) that utilizes adenosine as a preferred substrate. Slc29a1 promoted erythroblast survival and differentiation ex vivo. Targeted ablation of murine Slc29a1 in erythroblasts attenuated erythropoiesis and erythrocyte regeneration in response to acute anemia. Our results reveal a GATA factor-regulated SLC ensemble, with a nucleoside transporter component that promotes erythropoiesis and prevents anemia, and establish a mechanistic link between GATA factor and adenosine mechanisms. We propose that integration of the GATA factor-adenosine circuit with other components of the GATA factor-regulated SLC ensemble establishes the small molecule repertoire required for progenitor cells to efficiently generate erythrocytes.


Asunto(s)
Tranportador Equilibrativo 1 de Nucleósido/metabolismo , Eritropoyesis , Factores de Transcripción GATA/metabolismo , Adenosina/metabolismo , Animales , Células Cultivadas , Tranportador Equilibrativo 1 de Nucleósido/genética , Ratones , Ratones Endogámicos C57BL
6.
Molecules ; 28(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36677830

RESUMEN

Steroid hormone molecules may exhibit very different functionalities based on the associated functional groups and their 3D arrangements in space, i.e., absolute configurations and conformations. Infrared (IR) and vibrational circular dichroism (VCD) spectra of four different steroid hormones, namely dehydroepiandrosterone (DHEA), 17α-methyltestosterone (MTTT), (16α,17)-epoxyprogesterone (Epoxy-P4), and dehydroepiandrosterone acetate (AcO-DHEA), were measured in deuterated dimethyl sulfoxide and some also in carbon tetrachloride. Extensive conformational searches were carried out using the recent developed conformer-rotamer ensemble sampling tool (CREST) which also accounts for solvent effects using an implicit solvation model. All the CREST conformational candidates were then reoptimized at the B3LYP-D3BJ/def2-TZVPD with the PCM of solvent. The good agreements between the experimental IR and VCD spectra and the theoretical simulations provide a conclusive information about their conformational distribution and absolute configurations. The experimental and theoretical IR and VCD spectra of AcO-DHEA in the carbonyl and alkene stretching region showed some discrepancies, and the possible causes related to solvent effects, large amplitude motions and levels of theory used in the modelling were explored in detail. As part of the investigation, additional calculations at the B3LYP-D3BJ/6-31++G (2d,p) and B3LYP-D3BJ/cc-pVTZ levels, as well as some 'mixed' calculations with the double-hybrid functional B2PLYP-D3 were also carried out. The results indicate that the double-hybrid functional is important for predicting the correct IR band pattern in the carbonyl and alkene stretching region.

7.
Angew Chem Int Ed Engl ; 62(47): e202308827, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37802975

RESUMEN

Enzymatic catalysis with high efficiency allows them a great prospect in metabolite monitoring in living cells. However, complex tumor microenvironments, such as acidity, H2 O2 , and hypoxia, are bound to disturb catalytic reactions for misleading results. Here, we report a spatially compartmentalized artificial organelle to correct intratumoral glucose analysis, where the zeolitic imidazolate framework-8 immobilized glucose oxidase-horseradish peroxidase cascade core and catalase-directed shell act as signal transduction and guarding rooms respectively. The acid-digested core and stable shell provide appropriate spaces to boost biocatalytic efficiency with good tolerability. Notably, the endogenous H2 O2 is in situ decomposed to O2 by catalase, which not only overcomes the interference in signal output but also alleviates the hypoxic states to maximize glucose oxidation. The marked protective effect and biocompatibility render artificial organelles to correct the signal transduction for dynamic monitoring glucose in vitro and in vivo, achieving our goal of accurate intratumoral metabolite analysis.


Asunto(s)
Células Artificiales , Estructuras Metalorgánicas , Estructuras Metalorgánicas/metabolismo , Glucosa/análisis , Catalasa/metabolismo , Oxidación-Reducción , Glucosa Oxidasa/metabolismo
8.
J Antimicrob Chemother ; 77(7): 1960-1968, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35484082

RESUMEN

OBJECTIVES: To comprehensively analyse the prevalence of drug resistance and the transmission characteristics of CRF59_01B strains in infected patients in Guangdong, China. METHODS: CRF59_01B-infected individuals were recruited, and the HIV-1 pol region was amplified. Drug resistance-associated mutations (DRMs) and antiretroviral susceptibility were examined using the Stanford University HIV Drug Resistance Database to analyse pretreatment drug resistance (PDR) and acquired drug resistance (ADR). Genetic transmission networks were extracted from the maximum likelihood phylogenetic tree with Cluster Picker and visualized with Cytoscape. RESULTS: Two hundred and twenty-five CRF59_01B-infected individuals, comprising 35 ART-experienced and 190 ART-naive individuals, were recruited. No patients harboured PI DRMs, 5.33% (12/225) of the patients harboured NRTI DRMs and 11.11% (25/225) of the patients harboured NNRTI DRMs. The overall prevalence of strains with ADR was 51.43% (18/35), while the prevalence of strains with PDR was 2.63% (5/190). A total of 20 transmission networks, involving 25.78% (58/225) database-derived sequences, were identified. The networks ranged in size from 2 to 10 individuals, of which most (55.00%, 11/20) were made up of two individuals. Among the 225 study subjects, 9.78% (22/225) had 1 link and 16.00% (36/225) had ≥2 links. CONCLUSIONS: The overall prevalence of CRF59_01B strains with ADR among the ART-experienced patients was high. Although the overall prevalence of CRF59_01B strains with PDR among the ART-naive patients was low, it is necessary to remain vigilant regarding some important DRMs.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Seropositividad para VIH , VIH-1 , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , China/epidemiología , Farmacorresistencia Viral/genética , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Seropositividad para VIH/tratamiento farmacológico , VIH-1/genética , Humanos , Mutación , Filogenia , Prevalencia
9.
Nano Lett ; 21(4): 1879-1887, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33544604

RESUMEN

Benefiting from the maximum atom-utilization efficiency and distinct structural features, single-atom catalysts open a new avenue for the design of more functional catalysts, whereas their bioapplications are still in their infancy. Due to the advantages, platinum single atoms supported by cadmium sulfide nanorods (Pt SAs-CdS) are synthesized to build an ultrasensitive photoelectrochemical (PEC) biosensing platform. With the decoration of Pt SAs, the PEC signal of CdS is significantly boosted. Furthermore, theory calculations indicate the positively charged Pt SAs could change the charge distribution and increase the excited carrier density of CdS. Meanwhile, it also suggests that Cu2+ can severely hinder the photoexcitation and electron-hole separation of CdS. As a proof of concept, prostate-specific antigen is chosen as the target analyte to demonstrate the superiority of the Pt SAs-CdS-based PEC sensing system. As a result, the PEC biosensor based on Pt SAs-CdS exhibits outstanding detection sensitivity and promising applicability.


Asunto(s)
Técnicas Biosensibles , Nanotubos , Técnicas Electroquímicas , Humanos , Inmunoensayo , Límite de Detección , Masculino
10.
Anal Chem ; 93(48): 15982-15989, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34797969

RESUMEN

Rational design and construction of advanced sensing platforms for sensitive detection of H2O2 released from living cells is one of the challenges in the field of physiology and pathology. Noble metal clusters are a kind of nanomaterials with well-defined chemical composition and special atomic structures, which have been widely explored in catalysis, biosensing, and therapy. Compared with noble metal nanoparticles, noble metal clusters exhibit great potential in electrochemical biosensing due to their high atom utilization efficiency and abundant reactive active sites. Herein, Pt nanoclusters anchored on hollow carbon spheres (PtNCS/HCS) were successfully prepared for sensitive detection of H2O2. By tuning the ratio of Pt(0)/Pt(II) at different annealing temperatures, the optimized PtNCS/HCS-550 showed higher H2O2 reduction and oxidation catalytic activities than other control samples. Density functional theory calculations revealed that H2O2*can be better activated and dissociated in the Pt0II model featured with the co-existence of Pt(0)/Pt(II) and the key intermediates OOH*/OH* have a stronger interaction with the Pt0II model. As a concept application, the electrochemical biosensing platform was successfully applied to sensitive detection of H2O2 released from the cells.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Técnicas Electroquímicas , Peróxido de Hidrógeno , Oxidación-Reducción , Platino (Metal)
11.
Anal Chem ; 93(37): 12758-12766, 2021 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-34476936

RESUMEN

Inspired by the key role of the coordination environment in the catalytic activity of enzymes, a rational design of the coordination structure of active sites at the atom scale is expected to develop high-performance enzyme-like catalysts. Here, we design a simple model system involving pentacoordinated and tetracoordinated Fe-N-C single-atom catalysts (named NG-Heme and G-Heme, respectively) to investigate structure-activity relationships. NG-Heme with axial ligand-engineered Fe sites exhibits superior enzyme-like activity to G-Heme, achieving the goal of vivid mimicking of the active sites of peroxidase. Experiments and theoretical studies reveal that the enhanced intrinsic catalytic activity originates from the "push effect" of the additional axial ligand, which can strengthen the interaction between the active site and the intermediate. Based on the outstanding catalytic activity, an NG-Heme-linked immunosorbent assay was constructed for colorimetric detection of carcinoembryonic antigen, exhibiting satisfactory sensitivity and feasibility in the analysis of clinical samples.


Asunto(s)
Hemo , Peroxidasa , Catálisis , Inmunoensayo , Ligandos
12.
Virol J ; 18(1): 181, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34488793

RESUMEN

BACKGROUND: Transmitted drug resistance (TDR) that affects the effectiveness of the first-line antiretroviral therapy (ART) regimen is becoming prevalent worldwide. However, its prevalence and transmission among HIV-1 treatment-naïve patients in Guangdong, China are rarely reported. We aimed to comprehensively analyze the prevalence of TDR and the transmission clusters of HIV-1 infected persons before ART in Guangdong. METHODS: The HIV-1 treatment-naïve patients were recruited between January 2018 and December 2018. The HIV-1 pol region was amplified by reverse transcriptional PCR and sequenced by sanger sequencing. Genotypes, surveillance drug resistance mutations (SDRMs) and TDR were analyzed. Genetic transmission clusters among patients were identified by pairwise Tamura-Nei 93 genetic distance, with a threshold of 0.015. RESULTS: A total of 2368 (97.17%) HIV-1 pol sequences were successfully amplified and sequenced from the enrolled 2437 patients. CRF07_BC (35.90%, 850/2368), CRF01_AE (35.56%, 842/2368) and CRF55_01B (10.30%, 244/2368) were the main HIV-1 genotypes circulating in Guangdong. Twenty-one SDRMs were identified among fifty-two drug-resistant sequences. The overall prevalence of TDR was 2.20% (52/2368). Among the 2368 patients who underwent sequencing, 8 (0.34%) had TDR to protease inhibitors (PIs), 22 (0.93%) to nucleoside reverse transcriptase inhibitors (NRTIs), and 23 (0.97%) to non-nucleoside reverse transcriptase inhibitors (NNRTIs). Two (0.08%) sequences showed dual-class resistance to both NRTIs and NNRTIs, and no sequences showed triple-class resistance. A total of 1066 (45.02%) sequences were segregated into 194 clusters, ranging from 2 to 414 sequences. In total, 15 (28.85%) of patients with TDR were included in 9 clusters; one cluster contained two TDR sequences with the K103N mutation was observed. CONCLUSIONS: There is high HIV-1 genetic heterogeneity among patients in Guangdong. Although the overall prevalence of TDR is low, it is still necessary to remain vigilant regarding some important SDRMs.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral , Infecciones por VIH , VIH-1 , China/epidemiología , Estudios Transversales , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , VIH-1/efectos de los fármacos , VIH-1/genética , Humanos , Mutación , Filogenia , Prevalencia , Inhibidores de la Transcriptasa Inversa/uso terapéutico
13.
Hereditas ; 158(1): 29, 2021 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-34404481

RESUMEN

BACKGROUND: The formation of the Bicoid (Bcd) gradient in the early Drosophila is one of the most fascinating observations in biology and serves as a paradigm for gradient formation, yet its mechanism is still not fully understood. Two distinct models were proposed in the past, the SDD and the ARTS model. RESULTS: We define novel cis- and trans-acting factors that are indispensable for gradient formation. The first one is the poly A tail length of the bcd mRNA where we demonstrate that it changes not only in time, but also in space. We show that posterior bcd mRNAs possess a longer poly tail than anterior ones and this elongation is likely mediated by wispy (wisp), a poly A polymerase. Consequently, modulating the activity of Wisp results in changes of the Bcd gradient, in controlling downstream targets such as the gap and pair-rule genes, and also in influencing the cuticular pattern. Attempts to modulate the Bcd gradient by subjecting the egg to an extra nuclear cycle, i.e. a 15th nuclear cycle by means of the maternal haploid (mh) mutation showed no effect, neither on the appearance of the gradient nor on the control of downstream target. This suggests that the segmental anlagen are determined during the first 14 nuclear cycles. Finally, we identify the Cyclin B (CycB) gene as a trans-acting factor that modulates the movement of Bcd such that Bcd movement is allowed to move through the interior of the egg. CONCLUSIONS: Our analysis demonstrates that Bcd gradient formation is far more complex than previously thought requiring a revision of the models of how the gradient is formed.


Asunto(s)
Proteínas de Drosophila/genética , Drosophila/genética , Proteínas de Homeodominio/genética , Transactivadores/genética , Animales , Ciclina B/genética , Drosophila/embriología , Regulación del Desarrollo de la Expresión Génica , Poli A/genética , Polinucleotido Adenililtransferasa/genética , ARN Mensajero/genética
14.
J Antimicrob Chemother ; 75(7): 1925-1931, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32300784

RESUMEN

BACKGROUND: HIV-1 acquired drug resistance (ADR) has become a critical clinical and public health issue. Recently, HIV-1 CRF55_01B has been found more frequently in the MSM population. OBJECTIVE: To investigate the characteristics of HIV-1 drug resistance mutations (DRMs) and the extent of changes in drug susceptibility among ART-experienced CRF55_01B-infected adults of Guangdong. METHODS: ADR was tested for immediately in CRF55_01B-infected patients with virological failure. Demographic and epidemiological information was collected. DRMs and antiretroviral susceptibility were interpreted using the Stanford University HIV Drug Resistance Database HIVdb program. RESULTS: Overall, 162 (4.78%) CRF55_01B isolates were identified from 2013 to 2018. Among DRMs, M184V (43.83%) was the most frequent NRTI DRM, followed by K65R (23.46%), and V179E (98.77%) was the most frequent NNRTI DRM, followed by K103N (47.53%) and Y181C (14.81%). According to the HIVdb program, 79.01% of the CRF55_01B-infected patients carried mutations conferring low-level or higher drug resistance to any of the three classes of ART drugs. Among PI DRMs, only one mutation affording low-level resistance to nelfinavir was found (0.62%). Among NRTI DRMs, a high proportion of high-level resistance to lamivudine (58.64%) and emtricitabine (58.02%) was found. As regards NNRTIs, more than 75% of patients carried efavirenz and nevirapine DRMs. The percentages of high-level resistance were 70.99%, 63.58%, 22.22%, 17.90% and 4.32% for nevirapine, efavirenz, rilpivirine, doravirine and etravirine, respectively. CONCLUSIONS: High frequencies of DRMs and resistance were observed among CRF55_01B-infected patients failing ART in Guangdong, and interventions may be considered to minimize ecological contributions to ART.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Minorías Sexuales y de Género , Adulto , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , China/epidemiología , Farmacorresistencia Viral , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , VIH-1/genética , Homosexualidad Masculina , Humanos , Masculino , Mutación
15.
J Med Virol ; 92(12): 3295-3300, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32652607

RESUMEN

New approaches to increase HIV-1 testing and HIV-1 viral load (VL) monitoring are needed for people living with HIV (PLHIV) in China. The Xpert HIV-1 VL assay was prequalified by the World Health Organization in 2017 but has not been evaluated in China. A multicenter evaluation was conducted to assess the accuracy of the Cepheid Xpert HIV-1 VL assay compared to the Abbott RealTime HIV-1 assay in China. Overall agreement was seen in 558 of 562 specimens (99.29%) with a κ value of 0.962. Pearson's coefficient between the two assays was 0.943. Analyzed by the Bland-Altman method, the mean bias was -0.54 log10 copies/mL, and 94.05% results fell within the 95% confidence limit of agreement (-1.248 to 0.168 log10 copies/mL). The coefficient of variation of the Cepheid Xpert HIV-1 VL assay ranged from 0.61% to 1.55%, as determined by testing eight positive plasma specimens with three different lots on different days. Due to its simplicity, random-access, rapid turnaround time, and accuracy, the Xpert HIV-1 VL assay can be used in local hospitals and clinics that bear the burden of identifying and treating HIV patients in China.

16.
J Magn Reson Imaging ; 52(2): 448-458, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31943515

RESUMEN

BACKGROUND: Large-scale normative studies of pancreatic stiffness and potential influences have yet to be pursued via magnetic resonance elastography (MRE). PURPOSE: To determine normative MRE-based pancreatic stiffness values and to examine related influential factors. STUDY TYPE: Prospective. SUBJECTS: In all, 361 volunteers (men, 199; women, 162) with a median age of 54.0 years and a median body mass index (BMI) of 22.86 kg/m2 were prospectively recruited. Those with no histories of smoking, alcohol abuse, and diabetes mellitus (DM) were grouped as healthy volunteers, designating all others as positive controls. FIELD STRENGTH/SEQUENCE: Each volunteer underwent 3.0T pancreatic MRI at a frequency of 40 Hz. ASSESSMENT: Pancreatic stiffness values, pancreatic width and volume, waist circumference, and wave distance were measured in all subjects. STATISTICAL TESTS: Multiple linear regression analyses were performed to determine variables that influence MRE-determined stiffness. RESULTS: The mean pancreatic stiffness in all volunteers was 1.20 ± 0.16 kPa. Stiffness levels in positive control volunteers proved significantly greater than levels in healthy volunteers (1.29 ± 0.17 kPa vs. 1.14 ± 0.13 kPa; P < 0.001). In multiple linear regression analysis, sex (P = 0.004), BMI (P < 0.001), pancreatic width (P = 0.005), smoking (P < 0.001), alcohol abuse (P < 0.001), and DM (P = 0.001) emerged as significant independent factors impacting pancreatic stiffness. Smoking, alcohol abuse, DM, and wide pancreas were associated with greater pancreatic stiffness (coefficients = 0.202, 0.183, 0.149, and 0.160, respectively), while reduced pancreatic stiffness corresponded with female sex and larger BMI (coefficient = -0.155 and -0.192, respectively). DATA CONCLUSION: MRE-based pancreatic stiffness values are impacted by sex, BMI, pancreatic width, smoking, alcohol abuse, and DM. Reference values are essential for future clinical studies. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;52:448-458.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Páncreas/diagnóstico por imagen , Estudios Prospectivos , Reproducibilidad de los Resultados , Voluntarios
17.
Mater Today (Kidlington) ; 37: 112-125, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33093794

RESUMEN

The Blood-Brain Barrier (BBB), a unique structure in the central nervous system (CNS), protects the brain from bloodborne pathogens by its excellent barrier properties. Nevertheless, this barrier limits therapeutic efficacy and becomes one of the biggest challenges in new drug development for neurodegenerative disease and brain cancer. Recent breakthroughs in nanotechnology have resulted in various nanoparticles (NPs) as drug carriers to cross the BBB by different methods. This review presents the current understanding of advanced NP-mediated non-invasive drug delivery for the treatment of neurological disorders. Herein, the complex compositions and special characteristics of BBB are elucidated exhaustively. Moreover, versatile drug nanocarriers with their recent applications and their pathways on different drug delivery strategies to overcome the formidable BBB obstacle are briefly discussed. In terms of significance, this paper provides a general understanding of how various properties of nanoparticles aid in drug delivery through BBB and usher the development of novel nanotechnology-based nanomaterials for cerebral disease therapies.

18.
Eur Radiol ; 30(9): 5158-5169, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32346792

RESUMEN

OBJECTIVES: To identify quantitative imaging features of contrast-enhanced computed tomography (CE-CT) that may be prognostically favorable after resection of smaller (≤ 30 mm) pancreatic ductal adenocarcinomas (PDACs) located at head. METHODS: This retrospective study included two independent cohorts (discovery cohort, n = 212; test cohort, n = 100) of patients who underwent resection of head PDACs ≤ 30 mm and preoperative CE-CT. We examined tumor and surrounding parenchymal attenuation differences (deltas), and tumor attenuation changes across phases (ratios). Semantic features of PDACs were evaluated by two radiologists. Clinicopathologic and imaging features for predicting disease-free survival (DFS) and overall survival (OS) were analyzed via multivariate Lasso-penalized Cox proportional-hazards models. Survival rates were derived by Kaplan-Meier method. RESULTS: Imaging features achieved C-indices of 0.766 (discovery cohort) and 0.739 (test cohort) for DFS, and 0.790 (discovery cohort) and 0.772 (test cohort) for OS estimates through incorporation of clinicopathologic features. The most decisive imaging feature was delta 3, denoting attenuation differences between tumor and surrounding pancreas at pancreatic phase (DFS: HR = 2.122; OS: HR = 2.375; both p < 0.001). Compared with inconspicuous (low-delta-3, < 28 HU) tumors, conspicuous (high-delta-3) tumors correlated significantly with more aggressive histologic grades (p = 0.014) and less extensive tumor fibrous stromal fractions (p < 0.001). Patients with low-delta-3 tumors ≤ 20 mm experienced the most favorable outcomes (DFS, 36 months; OS, 42 months), whereas those with high-delta-3 tumors fared poorly, regardless of tumor size (DFS, 12 months; OS, 19 months). CONCLUSIONS: Quantifiable CT imaging features reflect heterogeneous fibrous stromal fractions and histologic grades of PDAC at head locations that help stratify patients with disparate clinical outcomes. KEY POINTS: • Quantitative and semantic imaging features achieved promising results for the prognosis of resected PDAC (≤ 30 mm) at head location, through incorporation of clinicopathologic features. • Attenuation difference at tumor-parenchyma interface (delta 3) emerged as the most decisive imaging feature, enabling further stratification of patients into distinct prognostic subtypes by tumor size. • High delta 3 signifies sharper contrast between tumor and surrounding pancreas, correlating with more aggressive histologic grades and less extensive tumor fibrous stromal fractions.


Asunto(s)
Carcinoma Ductal Pancreático/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Anciano , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Medios de Contraste , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Páncreas/diagnóstico por imagen , Páncreas/patología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tasa de Supervivencia , Tomografía Computarizada por Rayos X/métodos
19.
Wei Sheng Yan Jiu ; 49(5): 705-710, 2020 Sep.
Artículo en Zh | MEDLINE | ID: mdl-33070809

RESUMEN

OBJECTIVE: To explore the effect of pre-pregnancy weight and gestational weight gain in Chongqing City on birth weight of newborns. METHODS: Pregnant women were volunteered for the cohort study in 6 Maternal and Child Centers in Chongqing from January 2016 to June 2017, who were planning to be pregnant in latest 3 months. The basic information included height and weight of prepregnancy, first trimester, mid-trimester and third trimester of pregnancy, and pregnancy outcome were collected. ANOVA, chi square test and multi factor unconditional logistic regression model were used to analyze the data. RESULTS: In pre-pregnancy the major BMI of women were <18. 5(46. 74%, 1119/2394) and 18. 5≤BMI≤29. 99(47. 12%, 1128/2394), in first trimester of pregnancy, the figures were <18. 5(34. 46%, 825/2394) and 18. 5≤BMI≤29. 99(57. 77%, 1383/2394). The distribution BMI in above stages were statistically different(χ~2=74. 95, P<0. 01). The incidence of the low birth weight and macrosomia were 4. 51%(108/2394) and 6. 89%(165/2394). The average of neonatal birth weight, the low birth weight and macrosomia were statistically different(F=24. 18, P<0. 01) and(χ~2=66. 44, P<0. 01) comparisons among all prepregnancy BMI groups. The average birth weight of newborns, the low birth weight of the newborn and macrosomia were statistically different(F=11. 27, P<0. 01), and(χ~2=89. 53, P<0. 01) comparisons among all IOM groups of three stages of pregnancy. Low weight in pregnancy is the risk factor for low birth weight infants(RR=1. 90(95%CI 1. 27-2. 86)), while excessive gestational weight gain is the protective factor(RR=0. 66(95%CI 0. 46-0. 96)). Prepregnancy obesity(RR=3. 06(95%CI 1. 77-5. 31)) and excessive weight gain during pregnancy(RR=3. 60(95%CI 2. 48-5. 22)) were the risk factors for macrosomia. The above two factors, prepregnancy obesity and excessive weight gain during pregnancy interacted multiply. CONCLUSION: The figures of pre-pregnancy BMI are not equal to the BMI in first trimester of pregnancy. Low weight in pre-pregnancy is the risk factor for low birth weight infants, while excessive weight gain during pregnancy is the protective factor. Prepregnancy obesity and excessive weight gain during pregnancy are the risk factors for macrosomia. Prepregnancy obesity and excessive weight gain during pregnancy interacted multiply.


Asunto(s)
Ganancia de Peso Gestacional , Peso al Nacer , Índice de Masa Corporal , Niño , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Prospectivos
20.
Small ; 15(43): e1902485, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31468663

RESUMEN

Substantial progress has been made in applying nanotubes in biomedical applications such as bioimaging and drug delivery due to their unique architecture, characterized by very large internal surface areas and high aspect ratios. However, the biomedical applications of organic nanotubes, especially for those assembled from sequence-defined molecules, are very uncommon. In this paper, the synthesis of two new peptoid nanotubes (PepTs1 and PepTs2) is reported by using sequence-defined and ligand-tagged peptoids as building blocks. These nanotubes are highly robust due to sharing a similar structure to those of nontagged ones, and offer great potential to hold guest molecules for biomedical applications. The findings indicate that peptoid nanotubes loaded with doxorubicin drugs are promising candidates for targeted tumor cell imaging and chemo-photodynamic therapy.


Asunto(s)
Biomimética , Nanotubos/química , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Peptoides/farmacología , Fotoquimioterapia , Línea Celular Tumoral , Doxorrubicina/farmacología , Endocitosis/efectos de los fármacos , Humanos , Ligandos , Peptoides/química
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