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1.
ACS Catal ; 14(5): 3090-3102, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38449528

RESUMEN

Nucleosides are ubiquitous to life and are required for the synthesis of DNA, RNA, and other molecules crucial for cell survival. Despite the notoriously difficult organic synthesis of nucleosides, 2'-deoxynucleoside analogues can interfere with natural DNA replication and repair and are successfully employed as anticancer, antiviral, and antimicrobial compounds. Nucleoside 2'-deoxyribosyltransferase (dNDT) enzymes catalyze transglycosylation via a covalent 2'-deoxyribosylated enzyme intermediate with retention of configuration, having applications in the biocatalytic synthesis of 2'-deoxynucleoside analogues in a single step. Here, we characterize the structure and function of a thermophilic dNDT, the protein from Chroococcidiopsis thermalis (CtNDT). We combined enzyme kinetics with structural and biophysical studies to dissect mechanistic features in the reaction coordinate, leading to product formation. Bell-shaped pH-rate profiles demonstrate activity in a broad pH range of 5.5-9.5, with two very distinct pKa values. A pronounced viscosity effect on the turnover rate indicates a diffusional step, likely product (nucleobase1) release, to be rate-limiting. Temperature studies revealed an extremely curved profile, suggesting a large negative activation heat capacity. We trapped a 2'-fluoro-2'-deoxyarabinosyl-enzyme intermediate by mass spectrometry and determined high-resolution structures of the protein in its unliganded, substrate-bound, ribosylated, 2'-difluoro-2'-deoxyribosylated, and in complex with probable transition-state analogues. We reveal key features underlying (2'-deoxy)ribonucleoside selection, as CtNDT can also use ribonucleosides as substrates, albeit with a lower efficiency. Ribonucleosides are the building blocks of RNA and other key intracellular metabolites participating in energy and metabolism, expanding the scope of use of CtNDT in biocatalysis.

2.
Opt Express ; 32(2): 1231-1245, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38297679

RESUMEN

Comprehensive optical imaging of the intensity, phase, and birefringent information of the biological sample is important because important physical or pathological changes always accompany the changes in multiple optical parameters. Current studies lack such a metric that can present the comprehensive optical property of the sample in one figure. In this paper, a polarization state synthesis tomography (PoST) method, which is based on the principle of polarization state coherent synthesis and demodulation, is proposed to achieve full-field tomographic imaging of the comprehensive information (i.e., intensity, phase, and birefringence) of the biological sample. In this method, the synthesis of the polarization state is achieved by the time-domain full-field low coherence interferometer, where the polarization states of the sample beam and the reference beam are set to be orthogonal for the synthesis of the polarization state. The synthesis of the polarization state enables two functions of the PoST system: (1) Depth information of the sample can be encoded by the synthesized polarization state because only when the optical path length difference between the two arms is within the coherence length, a new polarization state can be synthesized; (2) Since the scattering coefficient, refractive index and the birefringent property of the sample can modulate the intensity and phase of the sample beam, the synthesized polarization state is sensitive to all these three parameters and can provide the comprehensive optical information of the sample. In this work, the depth-resolved ability and the comprehensive optical imaging metric have been demonstrated by the standard samples and the onion cells, demonstrating the potential application value of this method for further investigation of the important physical or pathological process of the biological tissues.

3.
Nat Commun ; 15(1): 156, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38168054

RESUMEN

Cell-free RNAs (cfRNAs) offer an opportunity to detect diseases from a transcriptomic perspective, however, existing techniques have fallen short in generating a comprehensive cell-free transcriptome profile. We develop a sensitive library preparation method that is robust down to 100 µl input plasma to analyze cfRNAs independent of their 5'-end modifications. We show that it outperforms adapter ligation-based method in detecting a greater number of cfRNA species. We perform transcriptome-wide characterizations in 165 lung cancer, 30 breast cancer, 37 colorectal cancer, 55 gastric cancer, 15 liver cancer, and 133 cancer-free participants and demonstrate its ability to identify transcriptomic changes occurring in early-stage tumors. We also leverage machine learning analyses on the differentially expressed cfRNA signatures and reveal their robust performance in cancer detection and classification. Our work sets the stage for in-depth study of the cfRNA repertoire and highlights the value of cfRNAs as cancer biomarkers in clinical applications.


Asunto(s)
Ácidos Nucleicos Libres de Células , Neoplasias Pulmonares , Humanos , Ácidos Nucleicos Libres de Células/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Transcriptoma/genética , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia de ARN/métodos , ARN , Biomarcadores de Tumor/genética
4.
Neurocrit Care ; 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37833519

RESUMEN

BACKGROUND: The relationship of fibrin(ogen) degradation products (FDPs) and potassium with the functional outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) is still uncertain. This study aims to evaluate the predictive value of a novel combination biomarker, the FDP-to-potassium ratio (FPR), for poor functional outcomes in patients with aSAH. METHODS: A total of 425 consecutive patients with aSAH at a single center were retrospectively enrolled in our study. An unfavorable outcome was defined as a modified Rankin Scale (mRS) score of 3-6 at 3 months after discharge. Univariate analysis and multivariable logistic regression were performed for baseline information and laboratory parameters recorded at admission. In addition, the receiver operating characteristic curve was plotted, and propensity score matching was performed based on the FPR. RESULTS: On the basis of mRS grade, 301 patients were classified as having favorable outcomes, and 124 patients were assessed as having unfavorable outcomes. FPR levels were significantly correlated with mRS grade (r[Spearman] = 0.410; P < 0.001). Multivariate logistic regression analysis showed that age (odds ratio [OR] 1.043, 95% confidence interval [CI] 1.016-1.071; P = 0.002), white blood cell count (OR 1.150, 95% CI 1.044-1.267; P = 0.005), potassium (OR 0.526, 95% CI 0.291-0.949; P = 0.033), World Federation of Neurosurgical Societies grade (OR 1.276, 95% CI 1.055-1.544; P = 0.012), and FPR (OR 1.219, 95% CI 1.102-1.349; P < 0.001) at admission were independently associated with poor functional outcomes. The DeLong test showed that the area under the receiver operating characteristic curve of FPR was higher than that of age, white blood cell count, potassium, World Federation of Neurosurgical Societies grade, or FDP alone, indicating that FPR had better predictive potential than these other variables. After 1:1 propensity score matching (FPR ≥ 1.45 vs. FPR < 1.45), the rate of poor prognosis was still significantly increased in the high-FPR group (48/121 [39.7%] vs. 16/121 [13.2%], P < 0.001). CONCLUSIONS: Fibrin(ogen) degradation product-to-potassium ratio is an independent predictor of poor outcomes for patients with aSAH and may be a promising tool for clinicians to evaluate patients' functional prognosis.

5.
Opt Lett ; 48(18): 4757-4760, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37707895

RESUMEN

To achieve accurate selection and synchronous imaging of blood vessels and lymph, a speckle spectrum contrast method (SSC) based on spectral-domain optical coherence tomography (SD-OCT) is proposed in this Letter. In this method, the time-lapse optical coherence tomography (OCT) intensity signal is transformed to the Fourier frequency domain. By analyzing the frequency spectrum of the time-lapse OCT intensity signal, a parameter called SSC signal, which represents the ratio of different intervals of the high frequency to the low frequency, is utilized to extract and contrast different types of the vessels in the biological tissues. In the SSC spectrum, the SSC signals of the static tissue, lymphatic vessels, and vascular vessels can be separated in three different frequency intervals, enabling differentiation and synchronous imaging of the lymphatic-vascular vessels. A mouse ear was used to demonstrate the feasibility and efficiency of this method. By using the SSC signal as the imaging parameter, the lymphatic and blood vessels of the mouse ear are differentiated and visualized simultaneously. This study shows the feasibility of the three-dimensional (3D) synchronous angio-lymphography based on the SSC method, which provides a tool to improve the understanding for disease research and treatment.


Asunto(s)
Linfografía , Tomografía de Coherencia Óptica , Animales , Ratones
6.
Int J Clin Pract ; 2023: 5562495, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37609664

RESUMEN

Background: Tuberculosis (TB), a multisystemic disease with protean presentation, remains a major global health problem. Although concurrent pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) cases are commonly observed clinically, knowledge regarding concurrent PTB-EPTB is limited. Here, a large-scale multicenter observational study conducted in China aimed to study the epidemiology of concurrent PTB-EPTB cases by diagnostically defining TB types and then implementing association rules analysis. Methods: The retrospective study was conducted at 21 hospitals in 15 provinces in China and included all inpatients with confirmed TB diagnoses admitted from Jan 2011 to Dec 2017. Association rules analysis was conducted for cases with concurrent PTB and various types of EPTB using the Apriori algorithm. Results: Evaluation of 438,979TB inpatients indicated PTB was the most commonly diagnosed (82.05%) followed by tuberculous pleurisy (23.62%). Concurrent PTB-EPTB was found in 129,422 cases (29.48%) of which tuberculous pleurisy was the most common concurrent EPTB type observed. The multivariable logistic regression models demonstrated that odds ratios of concurrent PTB-EPTB cases varied by gender and age group. For PTB cases with concurrent EPTB, the strongest association was found between PTB and concurrent bronchial tuberculosis (lift = 1.09). For EPTB cases with concurrent PTB, the strongest association was found between pharyngeal/laryngeal tuberculosis and concurrent PTB (lift = 1.11). Confidence and lift values of concurrent PTB-EPTB cases varied with gender and age. Conclusions: Numerous concurrent PTB-EPTB case types were observed, with confidence and lift values varying with gender and age. Clinicians should screen for concurrent PTB-EPTB in order to improve treatment outcomes.


Asunto(s)
Tuberculosis Extrapulmonar , Tuberculosis Pleural , Tuberculosis Pulmonar , Humanos , Tuberculosis Pleural/complicaciones , Tuberculosis Pleural/epidemiología , Estudios Retrospectivos , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/epidemiología , China/epidemiología
7.
Opt Lett ; 48(7): 1878-1881, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221789

RESUMEN

To achieve non-invasive and high effective resolution microvascular imaging in vivo, photothermal modulation speckle optical coherence tomography (PMS-OCT) imaging technology is proposed in this Letter to enhance the speckle signal of the bloodstream for improving the imaging contrast and image quality in the deeper depth of Fourier domain optical coherence tomography (FD-OCT). The results of simulation experiments proved that this photothermal effect could disturb and enhance the speckle signals, because the photothermal effect could modulate the sample volume to expand and change the refractive index of tissues, leading to the change in the phase of interference light. Therefore, the speckle signal of the bloodstream will also change. With this technology we obtain a clear cerebral vascular nondestructive image of a chicken embryo at a certain imaging depth. This technology expands the application fields of optical coherence tomography (OCT) especially in more complex biological structures and tissues, such as the brain, and provides a new way, to the best of our knowledge, for the application of OCT in brain science.


Asunto(s)
Encéfalo , Tomografía de Coherencia Óptica , Embrión de Pollo , Animales , Pollos , Simulación por Computador , Embrión de Mamíferos
8.
Cancer Chemother Pharmacol ; 91(5): 401-412, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37000221

RESUMEN

INTRODUCTION: Fluoropyrimidines, principally 5-fluorouracil (5-FU), remain a key component of chemotherapy regimens for multiple cancer types, in particular colorectal and other gastrointestinal malignancies. To overcome key limitations and pharmacologic challenges that hinder the clinical utility of 5-FU, NUC-3373, a phosphoramidate transformation of 5-fluorodeoxyuridine, was designed to improve the efficacy and safety profile as well as the administration challenges associated with 5-FU. METHODS: Human colorectal cancer cell lines HCT116 and SW480 were treated with sub-IC50 doses of NUC-3373 or 5-FU. Intracellular activation was measured by LC-MS. Western blot was performed to determine binding of the active anti-cancer metabolite FdUMP to thymidylate synthase (TS) and DNA damage. RESULTS: We demonstrated that NUC-3373 generates more FdUMP than 5-FU, resulting in a more potent inhibition of TS, DNA misincorporation and subsequent cell cycle arrest and DNA damage in vitro. Unlike 5-FU, the thymineless death induced by NUC-3373 was rescued by the concurrent addition of exogenous thymidine. 5-FU cytotoxicity, however, was only reversed by supplementation with uridine, a treatment used to reduce 5-FU-induced toxicities in the clinic. This is in line with our findings that 5-FU generates FUTP which is incorporated into RNA, a mechanism known to underlie the myelosuppression and gastrointestinal inflammation associated with 5-FU. CONCLUSION: Taken together, these results highlight key differences between NUC-3373 and 5-FU that are driven by the anti-cancer metabolites generated. NUC-3373 is a potent inhibitor of TS that also causes DNA-directed damage. These data support the preliminary clinical evidence that suggest NUC-3373 has a favorable safety profile in patients.


Asunto(s)
Neoplasias Colorrectales , Timidilato Sintasa , Humanos , Timidilato Sintasa/genética , Fluorodesoxiuridilato/farmacología , Fluorodesoxiuridilato/uso terapéutico , Fluorouracilo/uso terapéutico , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Antimetabolitos , Neoplasias Colorrectales/genética , ADN
9.
Emerg Microbes Infect ; 12(1): 2148564, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36377487

RESUMEN

BACKGROUND: Posterior oropharyngeal saliva (POS) is increasingly recognized as an alternative specimen for detecting respiratory pathogens. The accuracy of Xpert® MTB/RIF Ultra (X-Ultra), when performed on POS obtained from patients with paucibacillary pulmonary tuberculosis (TB) is unclear. METHODS: We consecutively recruited adults with symptoms suggestive of pulmonary TB who were negative by both smear microscopy and Xpert MTB/RIF (X-Classic). Each participant was required to provide one bronchoalveolar lavage fluid (BALF) and one POS specimen, respectively. Diagnostic performances of X-Ultra and X-Classic on POS were compared against clinical and mycobacterial reference standards. FINDINGS: 686 participants meeting inclusion criteria were consecutively enrolled into the study. The overall diagnostic sensitivities of X-Ultra and X-Classic on POS samples were 78.9% [95% confidence interval (CI): 72.8-83.8] and 56.4% (95% CI: 49.7-62.9), respectively; the specificities were 96.6% (95% CI: 94.3-98.1) for X-Ultra and 97.6 (95CI: 95.5-98.8) for X-Classic in POS specimens. Notably, the sensitivity of X-Ultra on POS was as sensitive as X-Classic on BALF against microbiological reference standard (78.9% VS 73.1%). Against clinical diagnosis as a reference standard, the sensitivities of X-Ultra and X-Classic on POS were 55.9% (95% CI: 50.5-61.2; 193/345) and 40.0% (95% CI: 34.8-45.4; 138/345), respectively. The risk of negative results with POS was dramatically increased with decreasing bacterial loads. CONCLUSIONS: The testing of POS using X-Ultra shows promise as a tool to identify patients with paucibacillary TB. Considering that bronchoscopy is a semi-invasive procedure, POS testing ahead of bronchoscopy, may decrease the need for bronchoscopic procedures, and the cost of care.


Asunto(s)
Antibióticos Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Adulto , Humanos , Antibióticos Antituberculosos/uso terapéutico , Mycobacterium tuberculosis/genética , Rifampin , Estudios Prospectivos , Sensibilidad y Especificidad , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/microbiología
10.
Open Med (Wars) ; 17(1): 1965-1972, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36561841

RESUMEN

Considerable attention has been focused on the clinical features of coronavirus disease 2019 (COVID-19), but it is also important for clinicians to differentiate it from influenza virus infections. In the present study, the rate of coexisting disease was lower in the severe COVID-19 group than in the influenza A group (p = 0.003). Radiologically, severe COVID-19 patients had fewer instances of pleural effusion (p < 0.001). Clinically, severe COVID-19 patients had relatively better disease severity scores, less secondary bacterial infections, shorter times to beginning absorption on computed tomography, but longer durations of viral shedding from the time of admission (p < 0.05). Although the more severe influenza A patients required noninvasive respiratory support, these two groups ultimately yielded comparable mortalities. Based on the multiple logistic regression analysis, severe COVID-19 infection was associated with a lower risk of severe acute respiratory distress syndrome [odds ratio (OR) 1.016, 95% [confidence interval (CI)] 1.001-1.032, p = 0.041] and a better pneumonia severity index (OR 0.945, 95% [CI] 0.905-0.986, p = 0.009); however, these patients exhibited longer durations of viral shedding (OR 1.192, 95% [CI] 1.047-1.357, p = 0.008) than patients with severe influenza A infection. In conclusion, the conditions of severe influenza A patients appeared to be more critical than that of severe COVID-19 patients. However, relatively lower mortalities of these two severe cases are expected in the context of sufficient medical supplies.

11.
BMC Immunol ; 23(1): 62, 2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36587204

RESUMEN

BACKGROUND: Tuberculosis infection is a major complication of silicosis, but there is no study on whether silicosis can affect the sensitivity of QuantiFERON-TB Gold In-Tube (QFT-GIT) assays. This study will analyze the relationship between silicosis and QFT-GIT, determine the main factor of the QFT-GIT sensitivity decrease in silicosis and explore the methods to increase the sensitivity. METHODS: Silicosis patients with positive tubercle bacillus cultures were collected. The QFT-GIT, flow cytometry and blocking antibodies were used. RESULTS: The sensitivity of QFT-GIT in silicosis patients (58.46%) was significantly decreased and the expression of PD-1 on T cells and CD56+NK cells in pulmonary tuberculosis combined with silicosis were higher than normal tuberculosis patients and silicosis only patients. Further analysis found that the ratio of PD-1+CD4+T and IFN-γwere negatively correlated and blockaded the PD-1 pathway with antibodies can restore the sensitivity of QFT-GIT in silicosis. CONCLUSIONS: This is the first study to analyze the relationship between immune exhaustion and QFT-GIT in silicosis and found that the sensitivity of QFT-GIT was decreased by the expression of PD-1 on lymphocytes. Antibody blocking experiments increased the expression of IFN-γ and provided a new method to improve the sensitivity of QFT in silicosis. The study also found that silicosis can increase PD-1 expression. As PD-1 functions in infectious diseases, it will promote immune exhaustion in silicosis and lead to tuberculosis from latent to active infection. The study provided theoretical evidence for the diagnosis and immunotherapy of silicosis complications, and it has great value in clinical diagnostics and treatment.


Asunto(s)
Tuberculosis Latente , Silicosis , Tuberculosis , Humanos , Receptor de Muerte Celular Programada 1 , Tuberculosis Latente/diagnóstico , Silicosis/diagnóstico , Silicosis/complicaciones , Anticuerpos Bloqueadores , Linfocitos , Prueba de Tuberculina/métodos
12.
Cell Death Discov ; 8(1): 353, 2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35941127

RESUMEN

We explored the potential activity of compound 16 (Cpd16), a novel small molecule Nrf2 activator, in hydrogen peroxide (H2O2)-stimulated osteoblasts. In the primary murine/human osteoblasts and MC3T3-E1 murine osteoblastic cells, Cpd16 treatment at micro-molar concentrations caused disassociation of Keap1-Nrf2 and Nrf2 cascade activation. Cpd16 induced stabilization of Nrf2 protein and its nuclear translocation, thereby increasing the antioxidant response elements (ARE) reporter activity and Nrf2 response genes transcription in murine and human osteoblasts. Significantly, Cpd16 mitigated oxidative injury in H2O2-stimulited osteoblasts. H2O2-provoked apoptosis as well as programmed necrosis in osteoblasts were significantly alleviated by the novel Nrf2 activator. Cpd16-induced Nrf2 activation and osteoblasts protection were stronger than other known Nrf2 activators. Dexamethasone- and nicotine-caused oxidative stress and death in osteoblasts were attenuated by Cpd16 as well. Cpd16-induced osteoblast cytoprotection was abolished by Nrf2 short hairpin RNA or knockout, but was mimicked by Keap1 knockout. Keap1 Cys151S mutation abolished Cpd16-induced Nrf2 cascade activation and osteoblasts protection against H2O2. Importantly, weekly Cpd16 administration largely ameliorated trabecular bone loss in ovariectomy mice. Together, Cpd16 alleviates H2O2-induced oxidative stress and death in osteoblasts by activating Nrf2 cascade.

13.
Biomed Opt Express ; 13(8): 4247-4260, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36032575

RESUMEN

Due to rod-like hydroxyapatite crystal organizations, dental enamel is optically anisotropic, i.e., birefringent. Healthy enamel is known to be intrinsically negatively birefringent. However, when demineralization of enamel occurs, a considerable number of inter-crystallite spaces would be created between the crystallites in the enamel, which could lead to a sign reversion in birefringence of the enamel structure. We propose that this sign reversion can be leveraged in polarization sensitive OCT (PSOCT) imaging to differentiate early caries lesions from healthy enamel. In this study using PSOCT, we first confirm that the change in birefringence sign (negative to positive) can lead to a 90-degree alteration in the local axis orientation because of the switch between the fast and slow optic axes. We then demonstrate, for the first time, that the local axis orientation can be utilized to map and visualize the WSLs from the healthy enamel with a unique contrast. Moreover, the sharp alteration in local axis orientation gives a clear boundary between the WSLs and the healthy enamel, providing an opportunity to automatically segment the three-dimensional WSLs from the healthy enamel, enabling the characterization of their size and depth information in an intuitive way, which may aid clinical decision making and treatment planning.

14.
Biomed Opt Express ; 13(6): 3629-3646, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35781964

RESUMEN

There remains a clinical need for an accurate and non-invasive imaging tool for intraoral evaluation of dental conditions. Optical coherence tomography (OCT) is a potential candidate to meet this need, but the design of current OCT systems limits their utility in the intraoral examinations. The inclusion of light-induced autofluorescence (LIAF) can expedite the image collection process and provides a large field of view for viewing the condition of oral tissues. This study describes a novel LIAF-OCT system equipped with a handheld probe designed for intraoral examination of microstructural (via OCT) and microvascular information (via OCT angiography, OCTA). The handheld probe is optimized for use in clinical studies, maintaining the ability to detect and image changes in the condition of oral tissue (e.g., hard tissue damage, presence of dental restorations, plaque, and tooth stains). The real-time LIAF provides guidance for OCT imaging to achieve a field of view of approximately 6.9 mm × 7.8 mm, and a penetration depth of 1.5 mm to 3 mm depending on the scattering property of the target oral tissue. We demonstrate that the proposed system is successful in capturing reliable depth-resolved images from occlusal and palatal surfaces and offers added design features that can enhance its usability in clinical settings.

15.
Ther Adv Respir Dis ; 16: 17534666221110346, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35796535

RESUMEN

BACKGROUND: Recently, the SARS-CoV-2 variant of concern, Omicron (B.1.1.529), was identified as responsible for a novel wave of COVID-19 worldwide. Here, we compared initial clinical features of hospitalized COVID-19 patients during recent wave (Omicron Variant) with those in ancestral variant wave (2020). METHODS: This is a cohort study of electronic health record (EHR) data from a signal center in the China. The clinical data of 116 cases of Omicron hospitalized in 2022 and 87 cases hospitalized in 2020 were collected. The comparisons were performed with the Mann-Whitney U test, Fisher exact test or the chi-square test, and multivariable logistic regression analysis. RESULTS: Clinically, compared with 2020-cohort, Omicron-cohort was more inclined to cluster in younger population and had more nonsymptomatic (25.0%) and nonsevere cases, as well as suffered from comparable extrapulmonary complication. Radiologically, although the major computed tomography (CT) findings of both cohorts were ground-glass opacities (GGOs), crazy-paving pattern was relatively less seen in the Omicron-cohort. Based on multiple logistic regression analysis, Omicron-cohort was associated with a lower risk of complaining with fever, the presence of lung opacity, and increased Sequential Organ Failure Assessment (SOFA) score. CONCLUSION: This study provided the data of different patterns of clinic characteristics and reduced severity from infections that occurred in Omicron variant as compared with the outbreak of the epidemic in 2020 wave (ancestral variant).


Asunto(s)
COVID-19 , SARS-CoV-2 , Estudios de Cohortes , Humanos , Tomografía Computarizada por Rayos X/métodos
16.
Nat Microbiol ; 7(7): 986-1000, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35725777

RESUMEN

Inositol lipids are ubiquitous in eukaryotes and have finely tuned roles in cellular signalling and membrane homoeostasis. In Bacteria, however, inositol lipid production is relatively rare. Recently, the prominent human gut bacterium Bacteroides thetaiotaomicron (BT) was reported to produce inositol lipids and sphingolipids, but the pathways remain ambiguous and their prevalence unclear. Here, using genomic and biochemical approaches, we investigated the gene cluster for inositol lipid synthesis in BT using a previously undescribed strain with inducible control of sphingolipid synthesis. We characterized the biosynthetic pathway from myo-inositol-phosphate (MIP) synthesis to phosphoinositol dihydroceramide, determined the crystal structure of the recombinant BT MIP synthase enzyme and identified the phosphatase responsible for the conversion of bacterially-derived phosphatidylinositol phosphate (PIP-DAG) to phosphatidylinositol (PI-DAG). In vitro, loss of inositol lipid production altered BT capsule expression and antimicrobial peptide resistance. In vivo, loss of inositol lipids decreased bacterial fitness in a gnotobiotic mouse model. We identified a second putative, previously undescribed pathway for bacterial PI-DAG synthesis without a PIP-DAG intermediate, common in Prevotella. Our results indicate that inositol sphingolipid production is widespread in host-associated Bacteroidetes and has implications for symbiosis.


Asunto(s)
Bacteroides thetaiotaomicron , Inositol , Animales , Bacterias/metabolismo , Bacteroides thetaiotaomicron/metabolismo , Bacteroidetes/genética , Inositol/metabolismo , Metabolismo de los Lípidos , Ratones , Fosfatidilinositoles/metabolismo , Esfingolípidos/metabolismo
17.
J Immunol Res ; 2022: 2943113, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35340584

RESUMEN

Objective: Multidrug-resistant tuberculosis (MDR-TB) causes persistent infection and challenges tuberculosis control worldwide. T cell-mediated immunity plays a critical role in controlling Mycobacterium tuberculosis (Mtb) infection, and therefore, enhancing Mtb-specific T cell immune responses represents a promising therapeutic strategy against TB. Cytokine-induced killer (CIK) immunotherapy is based on autologous infusion of in vitro expanded bulk T cells, which include both pathogen-specific and nonspecific T cells from patient peripheral blood mononuclear cells (PBMC) into TB patients. Preclinical mouse studies have shown that the adoptive T cell therapy inhibited Mtb infection. However, the efficacy of CIK immunotherapy in the treatment of MDR-TB infection has not been evaluated in clinical trials. Methods: We performed a retrospective study of MDR-TB patients who received CIK immunotherapy in combination with anti-TB chemotherapy and those who had standard chemotherapy. Results: Our results showed that CIK immunotherapy in combination with anti-TB chemotherapy treatment increased the conversion rate of sputum smear and Mtb culture, alleviated symptoms, improved lesion absorption, and increased recovery. The kinetics of serology and immunology index monitoring data showed good safety profiles for the CIK treatment. Conclusion: Our study has provided strong evidence that CIK immunotherapy in combination with anti-TB chemotherapy is beneficial for MDR-TB patients. A multicenter clinical trial is warranted to evaluate CIK as a new immune therapy for MDR-TB.


Asunto(s)
Células Asesinas Inducidas por Citocinas , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Animales , Humanos , Inmunoterapia/métodos , Ratones , Estudios Retrospectivos , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
18.
Sci Rep ; 12(1): 3963, 2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35273250

RESUMEN

Skin broadly protects the human body from undesired factors such as ultraviolet radiation and abrasion and helps conserve body temperature and hydration. Skin's elasticity and its level of anisotropy are key to its aesthetics and function. Currently, however, treatment success is often speculative and subjective, and is rarely based on skin's elastic properties because there is no fast and accurate non-contact method for imaging of skin's elasticity. Here we report on a non-contact and non-invasive method to image and characterize skin's elastic anisotropy. It combines acoustic micro-tapping optical coherence elastography (AµT-OCE) with a nearly incompressible transversely isotropic (NITI) model to quantify skin's elastic moduli. In addition, skin sites were imaged with polarization sensitive optical coherence tomography (PS-OCT) to help define fiber orientation. Forearm skin areas were investigated in five volunteers. Results clearly demonstrate elastic anisotropy of skin in all subjects. AµT-OCE has distinct advantages over competitive techniques because it provides objective, quantitative characterization of skin's elasticity without contact, which opens the door for broad translation into clinical use. Finally, we demonstrate that a combination of multiple OCT modalities (structural OCT, OCT angiography, PS-OCT and AµT-OCE) may provide rich information about skin and can be used to characterize scar.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Rayos Ultravioleta , Acústica , Anisotropía , Elasticidad , Diagnóstico por Imagen de Elasticidad/métodos , Humanos , Tomografía de Coherencia Óptica
19.
Viral Immunol ; 35(4): 291-302, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35196150

RESUMEN

In this study, B and T lymphocyte attenuator (BTLA) and herpesvirus entry mediator (HVEM) expression on the surface of circulating CD4+ T and CD8+ T cells of patients with chronic hepatitis B (CHB) was investigated to explore their relationship with hepatitis B virus (HBV) clinical parameters. Both BTLA and HVEM were significantly upregulated on CD4+ T and CD8+ T cells of CHB patients compared with healthy controls (p < 0.01). Intriguingly, in CHB patients, the percentage of BTLA expression was positively correlated with that of HVEM (CD4+ T cells: r = 0.5461, p < 0.001 and CD8+ T cells: r = 0.4206, p < 0.01). Moreover, the percentage of BTLA expression was positively correlated with the levels of aspartate aminotransferase (AST) (CD4+ T cells: r = 0.3136, p < 0.05 and CD8+ T cells: r = 0.3159, p < 0.05) and alanine aminotransaminase (ALT) (CD4+ T cells: r = 0.3177, p < 0.05 and CD8+ T cells: r = 0.3311, p < 0.05). At the same time, the percentage of HVEM expression was also positively correlated with AST levels (CD4+ T cells: r = 0.3721, p < 0.05 and CD8+ T cells: r = 0.3325, p < 0.05) and ALT (CD4+ T cells: r = 0.3689, p < 0.05 and CD8+ T cells: r = 0.3476, p < 0.05). However, the percentage of BTLA and HVEM expression did not show significant relevance to HBV viral load. Further study demonstrated that BTLA inhibitory signaling could significantly inhibit T cell proliferation, activation, and cytokine production under optimal T cell receptor signaling (p < 0.05). Thereby, our findings indicate that the increased BTLA and HVEM expression on the surface of CD4+ and CD8+ T cells might represent a certain clinical significance and be involved in CHB progression during T cell exhaustion.


Asunto(s)
Hepatitis B Crónica , Miembro 14 de Receptores del Factor de Necrosis Tumoral/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Hepatitis B Crónica/metabolismo , Humanos , Receptores Inmunológicos/metabolismo
20.
Int J Infect Dis ; 115: 79-85, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34781005

RESUMEN

AIMS: A high proportion of all patients with tuberculosis (TB) present with extrapulmonary TB (EPTB), including concurrent EPTB involving more than one extrapulmonary lesion site. However, previous reports only characterized lesions of single-site EPTB cases. This study aimed to investigate epidemiological characteristics and association rules of concurrent EPTB cases in China. METHODS: An observational multi-centre study of 208,214 patients with EPTB lesions was undertaken in China from January 2011 to December 2017. Multi-variable logistic regression analysis was used to identify associations between gender and concurrent EPTB, and age and concurrent EPTB. Association rules were analysed for significance using the Apriori algorithm. RESULTS: The most common EPTB lesion was tuberculous pleurisy (49.8%), followed by bronchial TB (14.8%) and tuberculous meningitis (7.6%). The most common type of concurrent EPTB was tuberculous pleurisy concurrent with tuberculous peritonitis (1.80%). In total, 22 association rules, including 20 strong association rules, were identified; among these, the highest confidence rates were found for tuberculous myelitis concurrent with tuberculous meningitis, and sacral TB concurrent with lumbar vertebral TB. The association rules of EPTB concurrent with other EPTB types were found to vary with gender and age. The confidence rate of tuberculous myelitis concurrent with tuberculous meningitis was higher in females (83.67%) than males, and was highest in patients aged 25-34 years (87.50%). CONCLUSIONS: Many types of concurrent EPTB were found. Greater awareness of concurrent EPTB disease characteristics is needed to ensure timely clinical diagnosis and treatment of this disease.


Asunto(s)
Peritonitis Tuberculosa , Tuberculosis Meníngea , Tuberculosis Pleural , China/epidemiología , Femenino , Humanos , Pacientes Internos , Masculino , Tuberculosis Meníngea/complicaciones , Tuberculosis Meníngea/epidemiología , Tuberculosis Pleural/complicaciones , Tuberculosis Pleural/epidemiología
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