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1.
Int Immunopharmacol ; 134: 112141, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38733819

RESUMEN

BACKGROUND: Novel coronaviruses constitute a significant health threat, prompting the adoption of vaccination as the primary preventive measure. However, current evaluations of immune response and vaccine efficacy are deemed inadequate. OBJECTIVES: The study sought to explore the evolving dynamics of immune response at various vaccination time points and during breakthrough infections. It aimed to elucidate the synergistic effects of epidemiological factors, humoral immunity, and cellular immunity. Additionally, regression curves were used to determine the correlation between the protective efficacy of the vaccine and the stimulated immune response. METHODS: Employing LASSO for high-dimensional data analysis, the study utilised four machine learning algorithms-logistical regression, random forest, LGBM classifier, and AdaBoost classifier-to comprehensively assess the immune response following booster vaccination. RESULTS: Neutralising antibody levels exhibited a rapid surge post-booster, escalating to 102.38 AU/mL at one week and peaking at 298.02 AU/mL at two weeks. Influential factors such as sex, age, disease history, and smoking status significantly impacted post-booster antibody levels. The study further constructed regression curves for neutralising antibodies, non-switched memory B cells, CD4+T cells, and CD8+T cells using LASSO combined with the random forest algorithm. CONCLUSION: The establishment of an artificial intelligence evaluation system emerges as pivotal for predicting breakthrough infection prognosis after the COVID-19 booster vaccination. This research underscores the intricate interplay between various components of immunity and external factors, elucidating key insights to enhance vaccine effectiveness. 3D modelling discerned distinctive interactions between humoral and cellular immunity within prognostic groups (Class 0-2). This underscores the critical role of the synergistic effect of humoral immunity, cellular immunity, and epidemiological factors in determining the protective efficacy of COVID-19 vaccines post-booster administration.

2.
Pharmacol Res ; 203: 107160, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38547937

RESUMEN

Immunostimulatory antibody conjugates (ISACs) as a promising new generation of targeted therapeutic antibody-drug conjugates (ADCs), that not only activate innate immunity but also stimulate adaptive immunity, providing a dual therapeutic effect to eliminate tumor cells. However, several ISACs are still in the early stages of clinical development or have already failed. Therefore, it is crucial to design ISACs more effectively to overcome their limitations, including high toxicity, strong immunogenicity, long development time, and poor pharmacokinetics. This review aims to summarize the composition and function of ISACs, incorporating current design considerations and ongoing clinical trials. Additionally, the review delves into the current issues with ISACs and potential solutions, such as adjusting the drug-antibody ratio (DAR) to improve the bioavailability of ISACs. By leveraging the affinity and bioavailability-enhancing properties of bispecific antibodies, the utility between antibodies and immunostimulatory agents can be balanced. Commonly used immunostimulatory agents may induce systemic immune reactions, and BTK (Bruton's tyrosine kinase) inhibitors can regulate immunogenicity. Finally, the concept of grafting ADC's therapeutic principles is simple, but the combination of payload, linker, and targeted functional molecules is not a simple permutation and combination problem. The development of conjugate drugs faces more complex pharmacological and toxicological issues. Standing on the shoulders of ADC, the development and application scenarios of ISAC are endowed with broader space.


Asunto(s)
Inmunoconjugados , Humanos , Inmunoconjugados/uso terapéutico , Inmunoconjugados/farmacología , Animales , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología
3.
Neurochem Res ; 49(3): 660-669, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38010603

RESUMEN

Hexavalent chromium (Cr (VI)), one of the most detrimental pollutants, has been ubiquitously present in the environment and causes serious toxicity to humans, such as hepatotoxicity, nephrotoxicity, pulmonary toxicity, and cardiotoxicity. However, Cr (VI)-induced neurotoxicity in primary neuron level has not been well explored yet. Herein, potassium dichromate (K2Cr2O7) was employed to examine the neurotoxicity of Cr (VI) in rat primary hippocampal neurons. MTT test was used to examine the neural viability. Mitochondrial dysfunction was assessed by the JC-1 probe and Mito-Tracker probe. DCFH-DA and Mito-SOX Red were utilized to evaluate the oxidative status. Bcl-2 family and MAPKs expression were investigated using Western blotting. The results demonstrated that Cr (VI) treatment dose- and time-dependently inhibited neural viability. Mechanism investigation found that Cr (VI) treatment causes mitochondrial dysfunction by affecting Bcl-2 family expression. Moreover, Cr (VI) treatment also induces intracellular reactive oxygen species (ROS) generation, DNA damage, and MAPKs activation in neurons. However, inhibition of ROS by glutathione (GSH) effectually balanced Bcl-2 family expression, attenuated DNA damage and the MAPKs activation, and eventually improved neural viability neurons. Collectively, these above results above suggest that Cr (VI) causes significant neurotoxicity by triggering mitochondrial dysfunction, ROS-mediated oxidative damage and MAKPs activation.


Asunto(s)
Enfermedades Mitocondriales , Estrés Oxidativo , Humanos , Ratas , Animales , Especies Reactivas de Oxígeno/metabolismo , Cromo/toxicidad , Glutatión/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
4.
Int J Biol Macromol ; 256(Pt 2): 128375, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38000581

RESUMEN

Portulaca oleracea L. (purslane) is a vegetable that contains a variety of active compounds with nutritional properties and has the potential to treat ulcerative colitis (UC). However, the mechanisms underlying the effects of Portulaca oleracea L. polysaccharide (POP) in alleviating UC remain unclear. In this study, we prepared an aqueous extract of purslane and separated a fraction with molecular weight >10 kDa using membrane separation. This fraction was used to isolate POP. The effect of POP on gut microbiota and colon transcriptome in dextran sulfate sodium-induced UC model mice was evaluated. POP treatment reduced inflammation and oxidative stress imbalance in UC mice. In addition, POP improved the intestinal barrier and regulated intestinal homeostasis. Importantly, POP was found to regulate gut microbiota, maintain the levels of retinol and short-chain fatty acids in the gut, promote the proliferation and differentiation of B cells in the colon, and increase the expression of immunoglobulin A. These results provide novel insights into the role of POP in regulating intestinal homeostasis, which should guide further development of POP as a functional food.


Asunto(s)
Colitis Ulcerosa , Colitis , Portulaca , Animales , Ratones , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Sulfato de Dextran , Homeostasis , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Modelos Animales de Enfermedad , Colon , Ratones Endogámicos C57BL
5.
Antioxidants (Basel) ; 12(7)2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37507939

RESUMEN

Purslane, a common wild vegetable, contains active substances with various biological functions. However, its effects have been under-investigated in ulcerative colitis (UC). Therefore, this study investigated the therapeutic effects of purslane macromolecular (POEM) and small molecular extracts (POES) on dextran sulfate sodium (DSS)-induced UC in mice. Membrane separation was used to obtain extracts of different molecular weights, and their compositional differences were compared using liquid chromatography-mass spectrometry (LC/MS). POEM contained more proteins and polysaccharides, whereas POES contained more organic acids and alkaloids. These differences in composition were directly responsible for the different degrees of remission of the alleviated UC in model mice. POEM may alleviate UC by regulating the antioxidant capacity and the gut microbiota, whereas the major alleviatory effect of POES was primarily related to the regulation of antioxidant capacity. The POEM and POES effects identified in this study provide a theoretical basis for the development of purslane as a functional food.

6.
Int J Med Sci ; 19(8): 1300-1306, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35928715

RESUMEN

Background: LncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) was competitive endogenous RNA (ceRNA) involved in various molecular processes for metastasis development in lung cancer. Single nucleotide polymorphisms (SNPs) in MALAT1 gene might be predictive markers for lung cancer. In our study, we selected rs619586 and rs3200401 in MALAT1 gene to explore their effects on lung cancer susceptibility. Methods: The case-control study included 444 lung cancer cases and 460 healthy controls. Genotyping was performed by Taqman allelic discrimination method. Logistic regression, Student t-test, and Chi-square test (χ2 ) were used to analyze the data. Results: The findings of the study showed that rs3200401 was significantly associated with the risk of non-small cell lung cancer (NSCLC) and lung squamous cell carcinoma (LUSC). Compared with homozygous CC genotype, CT heterozygous genotype decreased risk of NSCLC (Pa = 0.034) and LUSC (Pa = 0.025). In addition, no statistical association was detected between rs619586 and lung cancer susceptibility. The interactions between genes and cigarette smoking were discovered via crossover analysis. However, there were no remarkable gene-environment interactions in additive and multiplicative model. Conclusion: Rs3200401 in lncRNA MALAT1 was associated with the susceptibility of non-small-cell lung cancer and lung squamous cell carcinoma. The gene-environmental (cigarette smoking) interactions were not notable.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , ARN Largo no Codificante , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/genética , Estudios de Casos y Controles , China/epidemiología , Fumar Cigarrillos/efectos adversos , Fumar Cigarrillos/genética , Interacción Gen-Ambiente , Predisposición Genética a la Enfermedad/genética , Humanos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/genética , Polimorfismo de Nucleótido Simple/genética , ARN Largo no Codificante/genética
7.
Front Cardiovasc Med ; 9: 834975, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35651911

RESUMEN

This study aimed to examine the performance of the dual antiplatelet therapy (DAPT) score in two retrospective cohorts of post-percutaneous coronary intervention (PCI) patients and to explore whether incorporating additional biomarkers could further improve the predictive power of the DAPT score. In a retrospective derivation cohort of 4,798 PCI patients, the validity of DAPT score for stratifying ischemic/bleeding risks was explored. Then, the association between the baseline status of 54 laboratory test biomarkers and ischemic/bleeding events was revealed while adjusting for the DAPT score. Combinations of individual laboratory test biomarkers that were significantly associated with ischemic/bleeding events were explored to identify the ones that improved discrimination of ischemic and bleeding events when incorporated into DAPT score. Finally, the impact of the combination of biomarkers with DAPT score was validated in an independent retrospective validation cohort of 1,916 PCI patients. Patients with a high DAPT score (DAPT score ≥ 2) had significantly higher risk of ischemic events and significantly lower risk of bleeding than patients with a low DAPT score (DAPT score < 2). Moreover, the addition of aspartate aminotransferase (AST) and red cell distribution width CV (RDW-CV) into the DAPT score further improved discrimination of ischemia and bleeding. Furthermore, the incremental predictive value of AST + RDW-CV maintained with measurements was updated at post-baseline time points. DAPT score successfully stratified the risks of ischemia/bleeding post PCI in the current cohorts. Incorporation of AST + RDW-CV into the DAPT score further improved prediction for both ischemic and bleeding events.

8.
Nutrition ; 95: 111490, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35026483

RESUMEN

OBJECTIVES: We aimed to establish reference intervals for water-soluble vitamins determined by liquid chromatography tandem mass spectrometry to improve the diagnosis of vitamin deficiency and outcomes of associated conditions. METHODS: In this retrospective analysis of 24 810 specimens, we aimed to examine sex-, age-, and season-related variations in vitamin levels in different groups, set reference-value intervals for vitamin levels, and evaluate these reference values against those recommended by manufacturers. RESULTS: Levels of vitamins B3, B5, B6, B7, and B12 were higher, and those of vitamins B2, B9, and C were lower, in men than in women. There were seasonal variations in levels of vitamins B1, B3, B5, B6, B9, B12, and C. Levels of vitamins B1, B2, B3, B5, B6, B7, B9, and C differed across age groups; vitamin B1 displayed significant differences between ages 0 to 14 years and adults compared with reference change values. The lower limits of vitamins B1 (ages 15-100 y), B2, B3, B7, and C were lower, and that of vitamin B5 was higher, than the recommended reference values. Finally, the upper limits of vitamins B1, B3, B5, B6, and B7 were lower than the recommended values. CONCLUSIONS: For values obtained using liquid chromatography tandem mass spectrometry, the lower limits of reference intervals for vitamins B1 (ages 15-100 y), B2, B3, B7, and C should be lowered, that of vitamin B5 should be raised, and the upper limits of reference intervals for vitamins B1, B3, B5, B6, and B7 should be lowered.


Asunto(s)
Espectrometría de Masas en Tándem , Complejo Vitamínico B , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Cromatografía Liquida , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Valores de Referencia , Estudios Retrospectivos , Estaciones del Año , Espectrometría de Masas en Tándem/métodos , Complejo Vitamínico B/análisis , Agua , Adulto Joven
9.
J Tradit Chin Med ; 41(6): 927-934, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34939389

RESUMEN

OBJECTIVE: To investigate the protective effects of Zuogui Wan (ZGW) on bone loss induced by ovariectomy (OVX) and its mechanism via orexin-A and orexin receptors in the osteoporosis rat model. METHODS: Fifty Sprague-Dawley female rats were randomly divided into sham-operated (sham) group and four OVX subgroups. Rats subjected to sham and OVX were treated with the vehicle (OVX, 1 mL/100 g weight, n = 10), 17ß-estradiol (E2, 50 µg*kg-1*d-1), and ZGW at the doses of 2.3 (ZGW-L) and 4.6 (ZGW-H) g/kg/day lyophilized powder daily for 3 months, respectively. The serum biochemical parameters of 17ß-estrogen (17ß-E2), tartrate-resistant acid phosphatase (TRACP-5b) and bone alkaline phosphatase (BALP) were measured by enzyme-linked immunosorbent assay. Hematoxylin-eosin staining was used to detect the changes in the morphological structure in bones. Microcomputed tomography was used to evaluate the bone mineral density and microarchitecture of the distal femur. The gene or protein expression of orexin-A, orexin receptor 1 (OX1R), orexin receptor 2 (OX2R), osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were assayed by either quantitative polymerase chain reaction or Western blot analysis. RESULTS: Compared with the OVX group, ZGW could reduce the serum level of TRACP-5b and increased the serum levels of BALP and17ß-E2 (P < 0.01). Meanwhile, ZGW could prevent bone loss and improved bone trabecular microarchitecture by increasing the trabeculae structure thickness and trabecular number, and arranging the trabeculae structure properly. Compared with the OVX group, it was upregulated for the orexin-A and OX2R mRNA or protein expression from the hypothalamus and tibiae, and OPG in the tibiae of ZGW groups (P < 0.01, < 0.05), while downregulated for the OX1R mRNA and protein expression in the tibiae and hypothalamus and RANKL from the tibiae (P < 0.01). CONCLUSION: ZGW exhibited a protective effect for PMOP that may be mediated via orexin-A and orexin receptors regulation.


Asunto(s)
Hueso Esponjoso , Osteoporosis , Animales , Densidad Ósea , Hueso Esponjoso/metabolismo , Medicamentos Herbarios Chinos , Femenino , Humanos , Receptores de Orexina/genética , Orexinas/genética , Orexinas/farmacología , Orexinas/uso terapéutico , Osteoporosis/etiología , Osteoporosis/genética , Ovariectomía , Ratas , Ratas Sprague-Dawley , Microtomografía por Rayos X
10.
Front Public Health ; 9: 610280, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34046384

RESUMEN

Background: The COVID-19 global pandemic has posed unprecedented challenges to health care systems all over the world. The speed of the viral spread results in a tsunami of patients, which begs for a reliable screening tool using readily available data to predict disease progression. Methods: Multicenter retrospective cohort study was performed to develop and validate a triage model. Patient demographic and non-laboratory clinical data were recorded. Using only the data from Zhongnan Hospital, step-wise multivariable logistic regression was performed, and a prognostic nomogram was constructed based on the independent variables identifies. The discrimination and calibration of the model were validated. External independent validation was performed to further address the utility of this model using data from Jinyintan Hospital. Results: A total of 716 confirmed COVID-19 cases from Zhongnan Hospital were included for model construction. Men, increased age, fever, hypertension, cardio-cerebrovascular disease, dyspnea, cough, and myalgia are independent risk factors for disease progression. External independent validation was carried out in a cohort with 201 cases from Jinyintan Hospital. The area under the curve (AUC) was 0.787 (95% confidence interval [CI]: 0.747-0.827) in the training group and 0.704 (95% CI: 0.632-0.777) in the validation group. Conclusions: We developed a novel triage model based on basic and clinical data. Our model could be used as a pragmatic screening aid to allow for cost efficient screening to be carried out such as over the phone, which may reduce disease propagation through limiting unnecessary contact. This may help allocation of limited medical resources.


Asunto(s)
COVID-19 , Humanos , Modelos Logísticos , Masculino , Estudios Retrospectivos , SARS-CoV-2 , Triaje
11.
Front Oncol ; 11: 606477, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33796452

RESUMEN

This study was to assess the prognosis stratification of the clinical-pathologic staging system incorporating estrogen receptor (ER)-negative disease, the nuclear grade 3 tumor pathology (CPS + EG), Neo-Bioscore, and a modified Neo-Bioscore system in breast cancer patients after preoperative systemic therapy (PST). A retrospective multicenter cohort study was conducted from 12 participating hospitals' databases from 2006 to 2015. Five-year disease free survival (DFS), disease specific survival (DSS), and overall survival (OS) were calculated using Kaplan-Meier Method. Area under the curve (AUC) of the three staging systems was compared. Wald test and maximum likelihood estimates in Cox proportional hazards model were used for multivariate analysis. A total of 1,077 patients were enrolled. The CPS + EG, Neo-Bioscore, and modified Neo-Bioscore could all stratify the DFS, DSS, and OS (all P < 0.001). While in the same stratum of Neo-Bioscore scores 2 and 3, the HER2-positive patients without trastuzumab therapy had much poorer DSS (P = 0.013 and P values < 0.01, respectively) as compared to HER2-positive patients with trastuzumab therapy and HER2-negative patients. Only the modified Neo-Bioscore had a significantly higher stratification of 5-year DSS than PS (AUC 0.79 vs. 0.65, P = 0.03). So, the modified Neo-Bioscore could circumvent the limitation of CPS + EG or Neo-Bioscore. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT03437837.

12.
Chest ; 159(1): 270-281, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32653568

RESUMEN

BACKGROUND: Traditional methods for cardiopulmonary assessment of patients with coronavirus disease 2019 (COVID-19) pose risks to both patients and examiners. This necessitates a remote examination of such patients without sacrificing information quality. RESEARCH QUESTION: The goal of this study was to assess the feasibility of a 5G-based robot-assisted remote ultrasound system in examining patients with COVID-19 and to establish an examination protocol for telerobotic ultrasound scanning. STUDY DESIGN AND METHODS: Twenty-three patients with COVID-19 were included and divided into two groups. Twelve were nonsevere cases, and 11 were severe cases. All patients underwent a 5G-based robot-assisted remote ultrasound system examination of the lungs and heart following an established protocol. Distribution characteristics and morphology of the lung and surrounding tissue lesions, left ventricular ejection fraction, ventricular area ratio, pericardial effusion, and examination-related complications were recorded. Bilateral lung lesions were evaluated by using a lung ultrasound score. RESULTS: The remote ultrasound system successfully and safely performed cardiopulmonary examinations of all patients. Peripheral lung lesions were clearly evaluated. Severe cases of COVID-19 had significantly more diseased regions (median [interquartile range], 6.0 [2.0-11.0] vs 1.0 [0.0-2.8]) and higher lung ultrasound scores (12.0 [4.0-24.0] vs 2.0 [0.0-4.0]) than nonsevere cases of COVID-19 (both, P < .05). One nonsevere case (8.3%; 95% CI, 1.5-35.4) and three severe cases (27.3%; 95% CI, 9.7-56.6) were complicated by pleural effusions. Four severe cases (36.4%; 95% CI, 15.2-64.6) were complicated by pericardial effusions (vs 0% of nonsevere cases, P < .05). No patients had significant examination-related complications. INTERPRETATION: Use of the 5G-based robot-assisted remote ultrasound system is feasible and effectively obtains ultrasound characteristics for cardiopulmonary assessment of patients with COVID-19. By following established protocols and considering medical history, clinical manifestations, and laboratory markers, this system might help to evaluate the severity of COVID-19 remotely.


Asunto(s)
COVID-19/complicaciones , Cardiopatías/diagnóstico por imagen , Cardiopatías/etiología , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/etiología , Robótica , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Ultrasonografía/métodos
13.
Comput Biol Chem ; 88: 107360, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32841839

RESUMEN

BACKGROUND: Anatomical subsites always harbor specific biological features in carcinogenesis. The divergent prognosis of proximal gastric cancer (PGC) and distal gastric cancer (DGC) has been reported. The current study aimed to comprehensively interpret anatomic subsite-specific genomic profiles, which may improve the effectiveness of personalized management. METHODS: Survival and genomic data from the online Surveillance, Epidemiology, and End Results (SEER) and The Cancer Genome Atlas (TCGA) databases were queried for prognostic and genetic analysis, respectively. Propensity score matching (PSM) analysis was performed to balance patient epidemiological factors. Differentially expressed genes (DEGs) were analyzed using the DESeq algorithm. Functional enrichment was performed by the clusterProfiler package. The protein-protein interaction network of DEGs was predicted by the online STRING database. RESULTS: A total of 3,955 patient pairs were assembled by PSM in SEER data with even background characteristics. Prognostic analysis indicated worse overall survival of PGC than DGC (17 vs 20 months, p = 0.0002). Genetic analysis of TCGA database identified 280 DEGs, 90 of which were upregulated in the DGC group and the remaining 190 were upregulated in the PGC group. Functional enrichment analysis indicated that kallikrein serine protease activity, ion channel (Na+/Cl-) activity, and cytoskeleton constituent might be attributed to the poor prognosis observed in PGC. Furthermore, alcohol, retinol, and lipoprotein metabolism were the features for DGC malignancy. CONCLUSION: The current study first demonstrated that PGC exerts poorer survival outcome than DGC based on the SEER database. Further bioinformatic investigation depicts the specific genetic features for PGC and DGC, which may generate differences in tumor malignancy. Our findings provide promising genetic targets for future specific and individualized gastric cancer therapy.


Asunto(s)
Algoritmos , Neoplasias Gástricas/genética , Anciano , Biología Computacional , Bases de Datos Genéticas , Femenino , Humanos , Masculino , Neoplasias Gástricas/diagnóstico , Tasa de Supervivencia
14.
Precis Clin Med ; 3(2): 104-112, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35960675

RESUMEN

Objective: To analyse the impact and repercussions of the surge in healthcare demand in response to the COVID-19 pandemic, assess the potential effectiveness of various infection/disease control measures, and make projections on the best approach to exit from the current lockdown. Design: A four-compartment model was constructed for SARS-CoV-2 infection based on the Wuhan data and validated with data collected in Italy, the UK, and the US. The model captures the effectiveness of various disease suppression measures in three modifiable factors: (a) the per capita contact rate (ß) that can be lowered by means of social distancing, (b) infection probability upon contacting infectious individuals that can be lowered by wearing facemasks, personal hygiene, etc., and (c) the population of infectious individuals in contact with the susceptible population, which can be lowered by quarantine. The model was used to make projections on the best approach to exit from the current lockdown. Results: The model was applied to evaluate the epidemiological data and hospital burden in Italy, the UK, and the US. The control measures were identified as the key drivers for the observed epidemiological data through sensitivity analyses. Analysing the different lockdown exit strategies showed that a lockdown exit strategy with a combination of social separation/general facemask use may work, but this needs to be supported by intense monitoring which would allow re-introduction/tightening of the control measures if the number of new infected subjects increases again. Conclusions and relevance: Governments should act early in a swift and decisive manner for containment policies. Any lockdown exit will need to be monitored closely, with regards to the potential of lockdown reimplementation. This mathematical model provides a framework for major pandemics in the future.

15.
Precis Clin Med ; 3(4): 301-305, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35960681

RESUMEN

The role of subjects with asymptomatic SARS-CoV-2 infection in the current pandemic is not well-defined. Based on two different approaches to estimate the culminative attack rate (seroprevalence of antibodies against SARS-CoV-2, and a four compartment mathematical model) and the reported number of patients with COVID-19, the ratio of asymptomatic versus symptomatic SARS-CoV-2 infection was estimated to be 7 (95% CI: 2.8-12.4) in Wuhan, Hubei, China, the first epicenter of this pandemic, which has settled with no new cases. Together with detailed recording of the contact sources in a cohort of patients, and applying the estimations to an established mathematical model, the viral transmissibility of the subjects with asymptomatic SARS-CoV-2 infection is around 10% of that of the symptomatic patients (95% CI: 7.6%-12.3%). Public health measures/policies should address this important pool of infectious source in combat against this viral pandemic.

16.
ACS Infect Dis ; 5(6): 1001-1012, 2019 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-30882198

RESUMEN

MmpL3, an essential transporter involved in the export of mycolic acids, is the proposed target of a number of antimycobacterial inhibitors under development. Whether MmpL3 serves as the direct target of these compounds, however, has been called into question after the discovery that some of them dissipated the proton motive force from which MmpL transporters derive their energy. Using a combination of in vitro and whole-cell-based approaches, we here provide evidence that five structurally distinct MmpL3 inhibitor series, three of which impact proton motive force in Mycobacterium tuberculosis, directly interact with MmpL3. Medium- to high-throughput assays based on these approaches were developed to facilitate the future screening and optimization of MmpL3 inhibitors. The promiscuity of MmpL3 as a drug target and the mechanisms through which missense mutations located in a transmembrane region of this transporter may confer cross-resistance to a variety of chemical scaffolds are discussed in light of the exquisite vulnerability of MmpL3, its apparent mechanisms of interaction with inhibitors, and evidence of conformational changes induced both by the inhibitors and one of the most commonly identified resistance mutations in MmpL3.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Desarrollo de Medicamentos , Mycobacterium tuberculosis/efectos de los fármacos , Humanos , Proteínas de Transporte de Membrana , Pruebas de Sensibilidad Microbiana , Fuerza Protón-Motriz
17.
Cancer Manag Res ; 10: 4155-4161, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30323671

RESUMEN

OBJECTIVE: To examine the relationship between polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and susceptibility to lung cancer in a female Chinese population. METHOD: A hospital-based case-control study of 388 cases and 388 controls was conducted. Two polymorphisms in MTHFR were detected using TaqMan methods. RESULTS: The MTHFR C677T polymorphism was associated with the risk of lung cancer and lung adenocarcinoma. Carriers with the TT genotype of C677T were observed to have an increased risk of lung cancer and lung adenocarcinoma (the ORs were 1.550 and 1.588, respectively). By contrast, the A1298C polymorphism had a negative relationship with the risk of lung cancer and lung adenocarcinoma; compared with the AA genotype carriers, the CC genotype carriers had a lower risk of lung cancer and adenocarcinoma in the female Chinese population (ORs were 0.302 and 0.215, respectively). In the stratified analyses, we observed only the A1298C polymorphism in the CC genotype carriers with a statistically significant reduction in the risk of non-small-cell lung cancer, compared to the AA genotype carriers. No significant statistical association was found between the MTHFR gene polymorphisms and risk of the residual subtype of lung cancer. CONCLUSION: This study provides evidence that the MTHFR C677T polymorphism may contribute to the development of lung cancer and lung adenocarcinoma in a female Chinese population. However, the MTHFR A1298C polymorphism may be associated with the decreasing risk of lung cancer.

18.
Front Microbiol ; 9: 1547, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30042757

RESUMEN

Nontuberculous mycobacterial (NTM) pulmonary infections are emerging as a global health problem and pose a threat to susceptible individuals with structural or functional lung conditions such as cystic fibrosis, chronic obstructive pulmonary disease and bronchiectasis. Mycobacterium avium complex (MAC) and Mycobacterium abscessus complex (MABSC) species account for 70-95% of the pulmonary NTM infections worldwide. Treatment options for these pathogens are limited, involve lengthy multidrug regimens of 12-18 months with parenteral and oral drugs, and their outcome is often suboptimal. Development of new drugs and improved regimens to treat NTM infections are thus greatly needed. In the last 2 years, the screening of compound libraries against M. abscessus in culture has led to the discovery of a number of different chemotypes that target MmpL3, an essential inner membrane transporter involved in the export of the building blocks of the outer membrane of all mycobacteria known as the mycolic acids. This perspective reflects on the therapeutic potential of MmpL3 in Mycobacterium tuberculosis and NTM and the possible reasons underlying the outstanding promiscuity of this target. It further analyzes the physiological and structural factors that may account for the apparent looser structure-activity relationship of some of these compound series against M. tuberculosis compared to NTM.

19.
Int J Oncol ; 53(2): 469-476, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29845228

RESUMEN

Cancer stem cells (CSCs), also known as tumor-initiating cells, are a subpopulation of tumor cells that exhibit properties similar to those of normal stem cells. Oxygen is an important regulator of cellular metabolism; hypoxia-inducible factors (HIFs) mediate metabolic switches in cells in hypoxic environments. Hypoxia clearly has the potential to exert a significant effect on the maintenance and evolution of CSCs. Both HIF­1α and HIF­2α may contribute to the regulation of cellular adaptation to hypoxia and resistance to cancer therapies. This review provides an overview of the roles of HIFs in CSCs. HIF­1α and HIF­2α have significant prognostic and predictive value in the clinic and the concept of personalized medicine should be applied in designing clinical trials for HIF inhibitors.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , Animales , Hipoxia de la Célula , Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Pronóstico
20.
Biomed Pharmacother ; 103: 1052-1060, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29710663

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The deficiency of kidney Yin is the main pathogenesis of postmenopausal osteoporosis (PMOP) according to traditional Chinese medicine (TCM). Zuoguiwan (ZGW) is among the classical prescriptions in TCM and has been applied to various diseases that are due to deficiency of kidney Yin, including osteoporosis, fractures, menopausal syndromes. However, the underlying mechanism of ZGW in treating PMOP remains poorly understood. AIM OF THE STUDY: ZGW, a traditional Chinese prescription, has been used to nourish Yin and reinforce the kidney since ancient times. The investigation aimed to explore the mechanism of ZGW via the receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) signaling pathway as mediated by the ß2-adrenergic receptor (ß2AR) in an osteoporosis rat model. MATERIALS AND METHODS: An osteoporosis model induced by ovariectomy was established in rats. A total of 40 female Sprague-Dawley rats were randomly assigned into bilateral ovariectomy group (OVX), sham operated group (Sham), 17ß-estradiol-treated positive group (E2, 25 µg/kg/d), ZGW low-dose group (ZGW-L, 2.3 g/kg/d lyophilized powder) and ZGW high-dose group (ZGW-H, 4.6 g/kg/d lyophilized powder). The serum markers of bone turnover were measured using enzyme-linked immunosorbent assay (ELISA). The morphological structure changes in bones were detected through H&E staining. Local bone mineral density (BMD) and trabecular bone microarchitecture of the right distal femur were measured and evaluated by using micro-CT. Furthermore, the mRNA and protein expressions levels of ß2AR, OPG and RANKL were measured by qPCR and Western blot analysis. RESULTS: Compared with the OVX group, ZGW groups showed significantly reduced levels of serum tartrate-resistant acid phosphatase 5b (TRACP-5b) and ß-cross-linked c-telopeptide of type I collagen (ß-CTX) (P < 0.01), increased levels of serum bone-specific alkaline phosphatase (BALP) (P < 0.01) and OPG (P < 0.05), prevention of OVX-induced bone loss, and improved microarchitecture of the trabecular bone of distal femur. Moreover, ZGW mediated the osteoporosis syndrome by reducing the empty bone lacunae, promoting the ordered arrangement of trabeculae structure, and increasing the trabeculae structure thickness. Furthermore, in ZGW groups, the protein expression of OPG in the tibia was notably up-regulated (P < 0.01), whereas the mRNA and protein expression of ß2AR in the hippocampus (P < 0.01), and the protein expressions levels of ß2AR (P < 0.01) and RANKL (P < 0.05) in the tibia were down-regulated compared with OVX group. CONCLUSIONS: ZGW through its protective effects, stimulates bone formation and suppresses bone resorption. The underlying mechanism of ZGW in improving perimenopausal syndrome and increasing bone mass might be attributed to the regulation of RANKL/OPG, as mediated by ß2AR. Therefore, ZGW may be used as an alternative treatment for PMOP.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Osteoporosis/tratamiento farmacológico , Osteoprotegerina/metabolismo , Ligando RANK/metabolismo , Animales , Biomarcadores/metabolismo , Densidad Ósea/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Osteogénesis/efectos de los fármacos , Osteoporosis/metabolismo , Osteoporosis/patología , Ovariectomía , Ratas Sprague-Dawley , Transducción de Señal
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