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1.
Chemosphere ; 355: 141748, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38521109

RESUMEN

Sugarcane bagasse is one of the most common Vietnamese agricultural waste, which possesses a large percentage of cellulose, making it an abundant and environmentally friendly source for the fabrication of cellulose carbon aerogel. Herein, waste sugarcane bagasse was used to synthesize cellulose aerogel using different crosslinking agents such as urea, polyvinyl alcohol (PVA) and sodium alginate (SA). The 3D porous network of cellulose aerogels was constructed by intermolecular hydrogen bonding, which was confirmed by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption/desorption. Among the three cellulose aerogel samples, cellulose - SA aerogel (SB-CA-SA) has low density of 0.04 g m-3 and high porosity of 97.38%, leading to high surface area of 497.9 m2 g-1 with 55.67% micropores of activated carbon aerogel (SB-ACCA-SA). The salt adsorption capacity was high (17.87 mg g-1), which can be further enhanced to 31.40 mg g-1 with the addition of CNT. Moreover, the desalination process using the SB-ACCA-SA-CNT electrode was stable even after 50 cycles. The results show the great combination of cellulose from waste sugarcane bagasse with sodium alginate and carbon nanotubes in the fabrication of carbon materials as the CDI-utilized electrodes with high desalination capability and good durability.


Asunto(s)
Nanotubos de Carbono , Saccharum , Celulosa/química , Saccharum/química , Alginatos
2.
Pharm Dev Technol ; 29(3): 221-235, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38407140

RESUMEN

Photodynamic therapy (PDT) has emerged as a promising non invasive therapeutic approach for cancer treatment, offering unique advantages over conventional treatments. The combination of light activation and photosensitizing agents allows for targeted and localized destruction of cancer cells, reducing damage to surrounding healthy tissues. In recent years, the integration of nanoparticles with PDT has garnered significant attention due to their potential to enhance therapeutic outcomes. This review article aims to provide a comprehensive overview of the current state-of-the-art in utilizing nanoparticles for photodynamic therapy in cancer treatment. We summarized various nanoparticle-based approaches, their properties, and their implications in optimizing PDT efficacy, and discussed challenges and prospects in the field.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotosensibilizantes , Neoplasias/tratamiento farmacológico , Sistemas de Liberación de Medicamentos
3.
Front Neurol ; 14: 1124059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37305754

RESUMEN

Purpose: In this study, we described "PT for Sleep Apnea", a smartphone application for home-based physical therapy of patients with Obstructive Sleep Apnea (OSA). Methods: The application was created in a joint program between the University of Medicine and Pharmacy at Ho Chi Minh City (UMP), Vietnam, and National Cheng Kung University (NCKU), Taiwan. Exercises maneuvers were derived from the exercise program previously published by the partner group at National Cheng Kung University. They included exercises for upper airway and respiratory muscle training and general endurance training. Results: The application provides video and in-text tutorials for users to follow at home and a schedule function to assist the user in organizing the training program, which may improve the efficacy of home-based physical therapy in patients with Obstructive Sleep Apnea. Conclusion: In the future, our group plans to conduct a user study and randomized-controlled trials to investigate whether our application can benefit patients with OSA.

4.
Pharmaceutics ; 15(5)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37242604

RESUMEN

Lactoferrin (Lf)-a glycoprotein of the transferrin family-has been investigated as a promising molecule with diverse applications, including infection inhibition, anti-inflammation, antioxidant properties and immune modulation. Along with that, Lf was found to inhibit the growth of cancerous tumors. Owing to unique properties such as iron-binding and positive charge, Lf could interrupt the cancer cell membrane or influence the apoptosis pathway. In addition, being a common mammalian excretion, Lf offers is promising in terms of targeting delivery or the diagnosis of cancer. Recently, nanotechnology significantly enhanced the therapeutic index of natural glycoproteins such as Lf. Therefore, in the context of this review, the understanding of Lf is summarized and followed by different strategies of nano-preparation, including inorganic nanoparticles, lipid-based nanoparticles and polymer-based nanoparticles in cancer management. At the end of the study, the potential future applications are discussed to pave the way for translating Lf into actual usage.

5.
Heliyon ; 9(5): e16009, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37187906

RESUMEN

Background: The field of language teaching and learning has long recognized the role of vocabulary knowledge in all aspects of language proficiency and indicated that vocabulary beliefs and learning strategies play a pivotal role in learners' vocabulary development. As a result, understanding learners' beliefs and strategies in vocabulary learning is of paramount importance to language teachers. The Vocabulary Learning Questionnaire (VLQ) developed by Peter Gu in 2018 could be considered the most recent, validated instrument for the measurement of vocabulary learning beliefs and strategies. However, the VLQ contains too many items and is only available in English. The objectives of the study, therefore, are (1) to develop and validate a Vietnamese version of the VLQ which can exclude construct-irrelevant noises related to L2 comprehension, and (2) to reduce the number of items while retaining the key factors in the instruments. Methods: 722 Vietnamese university students took part in the study. Exploratory factor analyses (EFA) and confirmatory factor analyses (CFA) were examined with the free software Jamovi 2.3.13. Both Cronbach's alpha and McDonald's omega were employed to evaluate the factors' internal consistency. Results: Separate EFAs confirmed the two dimensions of vocabulary beliefs, explaining 62.6% of the total variance, and seven factors of vocabulary strategies, predicting 72.1% of the total variance. CFAs confirmed the hypothesized 9-dimensional structures of different vocabulary learning beliefs and strategies and offer cross-validation evidence for the Vietnamese VLQ. Reliability metrics demonstrated acceptable internal reliability for vocabulary belief and strategy sub-scales. Conclusion: The Vietnamese VLQ provides a validated measure of vocabulary beliefs and strategies. The 30-item version of the Vietnamese VLQ serves as a starting point for future research in the field of vocabulary learning and teaching in Vietnam.

6.
Bioengineering (Basel) ; 9(9)2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36134964

RESUMEN

The objective of the investigation was to understand the biochemical activities of hydrolysate of soybean milk protein (SMP). Hydrolysis was carried out by different concentrations of papain (0.008 g·L-1, 0.016 g·L-1, 0.032 g·L-1 and 0.064 g·L-1). The antioxidant capacity was measured by the ferric-reducing ability of plasma (FRAP) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assays. The anti-angiotensin activity of hydrolysate was measured by the recombinant angiotensin converting enzyme and substrate Abz-FRK(Dnp)-P. The contributions of the Kunitz trypsin inhibitor (KTI) and Bowman-Birk inhibitor (BBI) on antigenicity, and the in vitro digestion of papain-hydrolyzed SMP were studied. Rabbit polyclonal anti-KTI and anti-BBI antibodies together with peroxidase-labelled goat anti-Rb IgG secondary antibody were used to identify the antigenicity of KTI and BBI in unhydrolyzed and papain-hydrolyzed SMP. The antioxidant capacity and anti-angiotensin activity of SMP were increased after the papain hydrolysis of SMP. The KTI- and BBI-specific antigenicity were reduced in SMP by increasing the concentration of papain. However, there was interaction between papain-hydrolyzed SMP and trypsin in native gel, while interaction with chymotrypsin was absent. The interaction between trypsin and SMP was reduced due to the hydrolysis of papain in a concentration-dependent manner. According to the in vitro gastrointestinal digestion simulation protocol (Infogest), the digestibility of SMP was not statistically increased.

7.
Chemosphere ; 289: 133120, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34863724

RESUMEN

The SnO2/g-C3N4 composites were fabricated via an annealing mixture of g-C3N4 and SnO2, which were obtained from calcinating melamine and hydrothermal treatment of SnCl4 solution, respectively. The photocatalytic properties of g-C3N4/SnO2 were studied over the degradation of Rhodamine B (RhB) under visible light, which exhibits a significantly improved photocatalytic activity compared to the single components, g-C3N4 and SnO2. The enhancement in photocatalytic activity of SnO2/g-C3N4 could be described by the S-scheme pathway, in which the effective charge transfer between components is demonstrated toward the suppression in recombination of the photogenerated electron-hole pairs within redox potential conservation. Besides, a new criterion, photochemical space-time yield, was applied to evaluate the photocatalytic performance of our samples.


Asunto(s)
Electrones , Luz , Catálisis
8.
Cancer Cytopathol ; 128(8): 553-562, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32320527

RESUMEN

BACKGROUND: Approximately one third of needle biopsies that are performed to rule out malignancy of indeterminate pulmonary nodules detected radiologically during lung cancer screening are negative, thus exposing cancer-free patients to risks of pneumothorax, bleeding, and infection. A noninvasive confirmatory tool (eg, liquid biopsy) is urgently needed in the lung cancer diagnosis setting to stratify patients who should receive biopsy versus those who should be monitored. METHODS: A novel antigen-independent, 4-color fluorescence in situ hybridization (FISH)-based method was developed to detect circulating tumor cells (CTCs) with abnormalities in gene copy numbers in mononuclear cell-enriched peripheral blood samples from patients with (n = 107) and without (n = 100) lung cancer. RESULTS: Identification of CTCs using FISH probes at 10q22.3/CEP10 and 3p22.1/3q29 detected lung cancer cases with 94.2% accuracy, 89% sensitivity, and 100% specificity compared with biopsy. CONCLUSION: The high accuracy of this liquid biopsy method suggests that it may be used as a noninvasive decision tool to reduce the frequency of unnecessary needle biopsy in patients with benign pulmonary lesions.


Asunto(s)
Enfermedades Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico , Células Neoplásicas Circulantes , Tomografía Computarizada por Rayos X/métodos , Células A549 , Anciano , Aneuploidia , Diagnóstico Diferencial , Femenino , Humanos , Hibridación Fluorescente in Situ/métodos , Biopsia Líquida , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/genética , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/genética , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Sensibilidad y Especificidad
9.
Acta Biomater ; 94: 82-96, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31129358

RESUMEN

The expression of Toll-like receptors (TLRs) on antigen presenting cells, especially dendritic cells, offers several sensitive mediators to trigger an adaptive immune response, which potentially can be exploited to detect and eliminate pathogenic objects. Consequently, numerous agonists that target TLRs are being used clinically either alone or in combination with other therapies to strengthen the immune system in the battle against cancer. This review summarizes the roles of TLRs in tumor biology, and focuses on relevant TLR-dependent antitumor pathways and the conjugation of TLR agonists as adjuvants to nano- and micro-particles for boosting responses leading to cancer suppression and eradication. STATEMENT OF SIGNIFICANCE: Toll-like receptors (TLRs), which express on antigen presenting cells, such as dendritic cells and macrophages, play an important role in sensing pathogenic agents and inducing adaptive immunity. As a result, several TLR agonists have been investigating as therapeutic agents individually or in combination with other treatment modalities for cancer treatment through boosting the immune system. This review aims to focus on the roles of TLRs in cancer and TLR-dependent antitumor pathways as well as the use of different nano- or micro-particles bearing TLR agonists for tumor inhibition and elimination.


Asunto(s)
Inmunoterapia/métodos , Neoplasias/inmunología , Neoplasias/terapia , Receptores Toll-Like/metabolismo , Microambiente Tumoral , Inmunidad Adaptativa , Adyuvantes Inmunológicos , Animales , Células Presentadoras de Antígenos/inmunología , Células Dendríticas/metabolismo , Humanos , Sistema Inmunológico , Nanopartículas/química , ARN Mensajero/metabolismo , Transducción de Señal , Receptor Toll-Like 3/metabolismo , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 8/metabolismo , Receptor Toll-Like 9/metabolismo
10.
J Drug Target ; 27(2): 145-163, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29741964

RESUMEN

Immunotherapy holds tremendous promise for improving cancer treatment in which an appropriate stimulator may naturally trigger the immune system to control cancer. Up-to-date, adoptive T-cell therapy has received two new FDA approvals that provide great hope for some cancer patient groups. Nevertheless, expense and safety-related issues require further study to obtain insight into targets for efficient immunotherapy. The development of material science was largely responsible for providing a promising horizon to strengthen immunoengineering. In this review, we focus on T-cell characteristics in the context of the immune system against cancer and discuss several approaches of exploiting engineered particles to manipulate the responses of T cells and the tumour microenvironment.


Asunto(s)
Inmunoterapia , Nanopartículas/química , Neoplasias/terapia , Linfocitos T , Animales , Humanos , Microambiente Tumoral
11.
Cell Host Microbe ; 24(1): 133-145.e5, 2018 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-30001516

RESUMEN

The acquisition and development of the infant microbiome are key to establishing a healthy host-microbiome symbiosis. The maternal microbial reservoir is thought to play a crucial role in this process. However, the source and transmission routes of the infant pioneering microbes are poorly understood. To address this, we longitudinally sampled the microbiome of 25 mother-infant pairs across multiple body sites from birth up to 4 months postpartum. Strain-level metagenomic profiling showed a rapid influx of microbes at birth followed by strong selection during the first few days of life. Maternal skin and vaginal strains colonize only transiently, and the infant continues to acquire microbes from distinct maternal sources after birth. Maternal gut strains proved more persistent in the infant gut and ecologically better adapted than those acquired from other sources. Together, these data describe the mother-to-infant microbiome transmission routes that are integral in the development of the infant microbiome.


Asunto(s)
ADN Bacteriano/genética , Microbioma Gastrointestinal/genética , Tracto Gastrointestinal/microbiología , Relaciones Madre-Hijo , Adulto , Heces/microbiología , Femenino , Humanos , Lactante , Estudios Longitudinales , Metagenómica , Persona de Mediana Edad , Boca/microbiología , Piel/microbiología , Factores de Tiempo , Vagina/microbiología
12.
Int J Pharm ; 542(1-2): 253-265, 2018 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-29555438

RESUMEN

Crosstalk among immune cells has attracted considerable attention with the advent of immunotherapy as a novel therapeutic approach for challenging diseases, especially cancer, which is the leading cause of mortality worldwide. Dendritic cells-the key antigen-presenting cells-play a pivotal role in immunological response by presenting exogenous epitopes to T cells, which induces the self-defense mechanisms of the body. Furthermore, nanotechnology has provided promising ways for diagnosing and treating cancer in the last decade. The progress in nanoparticle drug carrier development, combined with enhanced understanding of the immune system, has enabled harnessing of anti-tumor immunity. This review focuses on the recent advances in nanotechnology that have improved the therapeutic efficacy of immunotherapies, with emphasis on dendritic cell physiology and its role in presenting antigens and eliciting therapeutic T cell response.


Asunto(s)
Células Dendríticas/inmunología , Inmunoterapia , Nanopartículas/uso terapéutico , Animales , Humanos
13.
Planta Med ; 84(3): 139-152, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29329463

RESUMEN

Ginsenoside Rh1 is one of major bioactive compounds extracted from red ginseng, which has been increasingly used for enhancing cognition and physical health worldwide. The objective of this study was to review the pharmacological effects of ginsenoside Rh1 in a systematic manner. We performed searches on eight electronic databases including MEDLINE (Pubmed), Scopus, Google Scholar, POPLINE, Global Health Library, Virtual Health Library, the System for Information on Grey Literature in Europe, and the New York Academy of Medicine Grey Literature Report to select the original research publications reporting the biological and pharmacological effects of ginsenoside Rh1 from in vitro and in vivo studies regardless of publication language and study design. Upon applying the inclusion and exclusion criteria, we included a total of 57 studies for our systemic review. Ginsenoside Rh1 exhibited the potent characteristics of anti-inflammatory, antioxidant, immunomodulatory effects, and positive effects on the nervous system. The cytotoxic effects of ginsenoside Rh1 were dependent on different types of cell lines. Other pharmacological effects including estrogenic, enzymatic, anti-microorganism activities, and cardiovascular effects have been mentioned, but the results were considerably diverged. A higher quality of evidence on clinical trial studies is highly recommended to confirm the consistent efficacy of ginsenoside Rh1.


Asunto(s)
Ginsenósidos/farmacología , Panax , Animales , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Estrógenos/farmacología , Humanos , Factores Inmunológicos/farmacología , Sistema Nervioso/efectos de los fármacos , Fitoterapia , Plantas Medicinales
14.
J Med Virol ; 90(5): 907-918, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28892235

RESUMEN

Daclatasvir, asunaprevir (ASV), and beclabuvir (BCV) are direct-acting antivirals (DAAs) for patients with hepatitis C virus genotype 1 infection. This systematic review and meta-analysis investigating the efficacy and safety of this three-drug combination in HCV genotype 1 infection. Eleven electronic search engines were searched for relevant publications. Studies were screened for eligibility and data was extracted. The outcomes were pooled as event rate and risk ratio (RR). The protocol was registered in PROSPERO (CRD42017054391). Among the included six studies, five studies were included for the meta-analysis (n = 1261). The three-drug combination showed a high response rate in naïve patients with sustained virologic response at week-12 posttreatment (SVR12 ) rate = 95.7% (95%CI [93.8-97.1]) and no difference detected by adding ribavirin (RBV) (the pooled RR = 0.98, 95%CI [0.90-1.08], P = 0.70) or comparing with interferon-experienced patients (RR = 1.02, 95%CI [0.98-1.07], P = 0.31) regardless the genotype 1 subtypes or IL28B genotype. Treatment failure was minimal and showed no difference regarding the previous comparisons. Increasing the dose or the duration did not show a significant increase in the efficacy. In conclusion, this analysis showed high response rates in HCV genotype 1-infected patients treated with daclatasvir, ASV, and BCV irrespective of RBV use, prior interferon-based therapy, or restriction on non-cirrhotic patients, IL28B genotype, or baseline resistance-associated variants.


Asunto(s)
Antivirales/administración & dosificación , Benzazepinas/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Imidazoles/administración & dosificación , Indoles/administración & dosificación , Isoquinolinas/administración & dosificación , Sulfonamidas/administración & dosificación , Antivirales/efectos adversos , Benzazepinas/efectos adversos , Carbamatos , Quimioterapia Combinada/efectos adversos , Quimioterapia Combinada/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Humanos , Imidazoles/efectos adversos , Indoles/efectos adversos , Isoquinolinas/efectos adversos , Pirrolidinas , Sulfonamidas/efectos adversos , Respuesta Virológica Sostenida , Resultado del Tratamiento , Valina/análogos & derivados
15.
J Mech Behav Biomed Mater ; 77: 527-533, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29049973

RESUMEN

The bio-chemo-mechanical model has many applications in modelling cell contractility. In simulations this model usually is coupled to the continuum mechanics of the cell by defining a large number of directions for stress fibres at each point. In this paper, another representation for coupling the biochemical processes in the bio-chemo-mechanical model is introduced. Using a quadratic form to represent the angular dependency of the activation level, the model's number of degrees of freedom is significantly reduced. Numerical results similar to the original representation are obtained while a significant improvement in computation time is achieved.


Asunto(s)
Simulación por Computador , Modelos Biológicos , Contracción Muscular , Diseño de Prótesis , Fibras de Estrés/fisiología , Actinas/química , Fenómenos Biomecánicos , Módulo de Elasticidad , Humanos , Miosinas/química , Probabilidad , Programas Informáticos , Estrés Mecánico , Resistencia a la Tracción
16.
Am J Cardiovasc Drugs ; 18(2): 93-102, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28660556

RESUMEN

INTRODUCTION: The efficacy of endothelin receptor antagonists (ERAs) in the management of Eisenmenger syndrome (ES) remains controversial. The aim of this study is to systemically review the safety and effects of ERAs in improving the quality of life and basic cardiac functions of these patients. METHODS: Twelve databases were searched, including PubMed, Web of Science, Scopus, Virtual Health Library, World Health Organization (WHO) Global Health Library, Google Scholar, POPLINE, Systems for Information of Grey Literature in Europe, New York Academy of Medicine, ClinicalTrials.gov, metaRegister of Controlled Trials and the WHO International Clinical Trials Registry Platform, through August 2016. We included randomized clinical trials addressing the effect of ERAs on cardiac functions in patients with ES. The quality of studies was assessed using the Cochrane Collaboration tool. RESULTS: We included two trials represented by four papers, of which three papers reported the efficacy of bosentan against placebo and one paper reported the results of a combination of bosentan and sildenafil versus placebo and bosentan. One trial showed a significant effect of bosentan treatment over placebo on indexed pulmonary vascular resistance and mean pulmonary artery pressure, but a non-significant increase in 6-min walk distance and a non-significant effect on systemic pulse oximetry. The other trial reported the safe but non-significant effect of combination therapy of bosentan and sildenafil compared with bosentan and placebo. CONCLUSIONS: This study demonstrated safety and improved hemodynamic effects of bosentan in ES, with a controversial effect on exercise capacity. Further randomized controlled trials with longer follow-up duration are needed to confirm these results.


Asunto(s)
Antihipertensivos/uso terapéutico , Complejo de Eisenmenger/tratamiento farmacológico , Antagonistas de los Receptores de Endotelina/uso terapéutico , Sulfonamidas/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Bosentán , Ensayos Clínicos como Asunto , Humanos , Calidad de Vida , Citrato de Sildenafil/uso terapéutico , Vasodilatadores/uso terapéutico
18.
Artículo en Inglés | MEDLINE | ID: mdl-28649415

RESUMEN

Psoriasis is an immune-mediated inflammatory skin disease that has been associated with cutaneous microbial dysbiosis by culture-dependent investigations and rRNA community profiling. We applied, for the first time, high-resolution shotgun metagenomics to characterise the microbiome of psoriatic and unaffected skin from 28 individuals. We demonstrate psoriatic ear sites have a decreased diversity and psoriasis is associated with an increase in Staphylococcus, but overall the microbiomes of psoriatic and unaffected sites display few discriminative features at the species level. Finer strain-level analysis reveals strain heterogeneity colonisation and functional variability providing the intriguing hypothesis of psoriatic niche-specific strain adaptation or selection. Furthermore, we accessed the poorly characterised, but abundant, clades with limited sequence information in public databases, including uncharacterised Malassezia spp. These results highlight the skins hidden diversity and suggests strain-level variations could be key determinants of the psoriatic microbiome. This illustrates the need for high-resolution analyses, particularly when identifying therapeutic targets. This work provides a baseline for microbiome studies in relation to the pathogenesis of psoriasis.

19.
mSystems ; 2(1)2017.
Artículo en Inglés | MEDLINE | ID: mdl-28144631

RESUMEN

The gut microbiome becomes shaped in the first days of life and continues to increase its diversity during the first months. Links between the configuration of the infant gut microbiome and infant health are being shown, but a comprehensive strain-level assessment of microbes vertically transmitted from mother to infant is still missing. We collected fecal and breast milk samples from multiple mother-infant pairs during the first year of life and applied shotgun metagenomic sequencing followed by computational strain-level profiling. We observed that several specific strains, including those of Bifidobacterium bifidum, Coprococcus comes, and Ruminococcus bromii, were present in samples from the same mother-infant pair, while being clearly distinct from those carried by other pairs, which is indicative of vertical transmission. We further applied metatranscriptomics to study the in vivo gene expression of vertically transmitted microbes and found that transmitted strains of Bacteroides and Bifidobacterium species were transcriptionally active in the guts of both adult and infant. By combining longitudinal microbiome sampling and newly developed computational tools for strain-level microbiome analysis, we demonstrated that it is possible to track the vertical transmission of microbial strains from mother to infants and to characterize their transcriptional activity. Our work provides the foundation for larger-scale surveys to identify the routes of vertical microbial transmission and its influence on postinfancy microbiome development. IMPORTANCE Early infant exposure is important in the acquisition and ultimate development of a healthy infant microbiome. There is increasing support for the idea that the maternal microbial reservoir is a key route of microbial transmission, and yet much is inferred from the observation of shared species in mother and infant. The presence of common species, per se, does not necessarily equate to vertical transmission, as species exhibit considerable strain heterogeneity. It is therefore imperative to assess whether shared microbes belong to the same genetic variant (i.e., strain) to support the hypothesis of vertical transmission. Here we demonstrate the potential of shotgun metagenomics and strain-level profiling to identify vertical transmission events. Combining these data with metatranscriptomics, we show that it is possible not only to identify and track the fate of microbes in the early infant microbiome but also to investigate the actively transcribing members of the community. These approaches will ultimately provide important insights into the acquisition, development, and community dynamics of the infant microbiome.

20.
Genome Res ; 27(4): 626-638, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28167665

RESUMEN

Among the human health conditions linked to microbial communities, phenotypes are often associated with only a subset of strains within causal microbial groups. Although it has been critical for decades in microbial physiology to characterize individual strains, this has been challenging when using culture-independent high-throughput metagenomics. We introduce StrainPhlAn, a novel metagenomic strain identification approach, and apply it to characterize the genetic structure of thousands of strains from more than 125 species in more than 1500 gut metagenomes drawn from populations spanning North and South American, European, Asian, and African countries. The method relies on per-sample dominant sequence variant reconstruction within species-specific marker genes. It identified primarily subject-specific strain variants (<5% inter-subject strain sharing), and we determined that a single strain typically dominated each species and was retained over time (for >70% of species). Microbial population structure was correlated in several distinct ways with the geographic structure of the host population. In some cases, discrete subspecies (e.g., for Eubacterium rectale and Prevotella copri) or continuous microbial genetic variations (e.g., for Faecalibacterium prausnitzii) were associated with geographically distinct human populations, whereas few strains occurred in multiple unrelated cohorts. We further estimated the genetic variability of gut microbes, with Bacteroides species appearing remarkably consistent (0.45% median number of nucleotide variants between strains), whereas P. copri was among the most plastic gut colonizers. We thus characterize here the population genetics of previously inaccessible intestinal microbes, providing a comprehensive strain-level genetic overview of the gut microbial diversity.


Asunto(s)
Genoma Humano , Metagenoma , Microbiota , Algoritmos , Bacteroides/genética , Bacteroides/aislamiento & purificación , Eubacterium/genética , Eubacterium/aislamiento & purificación , Humanos , Tipificación Molecular/métodos , Polimorfismo Genético , Prevotella/genética , Prevotella/aislamiento & purificación , Análisis de Secuencia de ADN/métodos
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