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1.
Gut ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051205

RESUMO

OBJECTIVE: Fusobacteria are not common nor relatively abundant in non-colorectal cancer (CRC) populations, however, we identified multiple Fusobacterium taxa nearly absent in western and rural populations to be comparatively more prevalent and relatively abundant in southern Chinese populations. We investigated whether these represented known or novel lineages in the Fusobacterium genus, and assessed their genomes for features implicated in development of cancer. METHODS: Prevalence and relative abundances of fusobacterial species were calculated from 3157 CRC and non-CRC gut metagenomes representing 16 populations from various biogeographies. Microbial genomes were assembled and compared with existing reference genomes to assess novel fusobacterial diversity. Phylogenetic distribution of virulence genes implicated in CRC was investigated. RESULTS: Irrespective of CRC disease status, southern Chinese populations harboured increased prevalence (maximum 39% vs 7%) and relative abundances (average 0.4% vs 0.04% of gut community) of multiple recognised and novel fusobacterial taxa phylogenetically distinct from Fusobacterium nucleatum. Genomes assembled from southern Chinese gut metagenomes increased existing fusobacterial diversity by 14.3%. Homologues of the FadA adhesin linked to CRC were consistently detected in several monophyletic lineages sister to and inclusive of F. varium and F. ulcerans, but not F. mortiferum. We also detected increased prevalence and relative abundances of F. varium in CRC compared with non-CRC cohorts, which together with distribution of FadA homologues supports a possible association with gut disease. CONCLUSION: The proportion of fusobacteria in guts of southern Chinese populations are higher compared with several western and rural populations in line with the notion of environment/biogeography driving human gut microbiome composition. Several non-nucleatum taxa possess FadA homologues and were enriched in CRC cohorts; whether this imposes a risk in developing CRC and other gut diseases deserves further investigation.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32017248

RESUMO

BACKGROUND AND AIM: Inflammatory bowel disease (IBD) patients are at risk for recurrent Clostridium difficile infection (RCDI). We aimed to evaluate the potential health economic and clinical outcomes of four strategies for management of RCDI in IBD patients from the perspective of public health-care provider in Hong Kong. METHODS: A decision-analytic model was designed to simulate outcomes of adult IBD patients with first RCDI treated with vancomycin, vancomycin plus bezlotoxumab, fidaxomicin and fecal microbiota transplantation (FMT). Model inputs were derived from literature and public data. Primary model outcomes were C. difficile infection (CDI)-related direct medical cost and quality-adjusted life-years (QALYs) loss. Base-case and sensitivity analysis were performed. RESULTS: Comparing to vancomycin, fidaxomicin and vancomycin plus bezlotoxumab, FMT saved 0.00318, 0.00149 and 0.00306 QALYs and reduced cost by USD3180, USD3790 and USD5514, respectively, in base-case analysis. In probabilistic sensitivity analysis, FMT was cost-saving when comparing to vancomycin, fidaxomicin and vancomycin plus bezlotoxumab by USD3765 (95% confidence interval [CI] 3732-3798; P < 0.001), USD3854 (95%CI 3827-3883; P < 0.001) and USD6501 (95%CI 6465-6,536; P < 0.001), respectively. The QALYs saved by FMT (vs vancomycin) were 0.00386 QALYs (95%CI 0.00384-0.00388; P < 0.001), (vs fidaxomicin) 0.00179 QALYs (95%CI 0.00177-0.00180; P < 0.001) and (vs vancomycin plus bezlotoxumab) 0.00376 QALYs (95%CI 0.00374-0.00378; P < 0.001). FMT was found to save QALYs at lower cost in 99.3% (vs vancomycin), 99.7% (vs fidaxomicin) and 100.0% (vs vancomycin plus bezlotoxumab) of the 10 000 Monte Carlo simulations. CONCLUSIONS: FMT for IBD patients with RCDI appeared to save both direct medical cost and QALYs when comparing to vancomycin (with or without bezlotoxumab) and fidaxomicin.

3.
J Virol ; 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996427

RESUMO

Human papillomavirus (HPV) type 58 is the third most commonly detected HPV type in cervical cancer among Eastern Asians. Our previous international epidemiological studies revealed that a HPV58E7 natural variant, T20I/G63S (designated as V1), was associated with a higher risk of cervical cancer. We recently showed that V1 possesses a greater ability to immortalise and transform primary cells, as well as degrading pRB more effectively than the prototype and other common variants. In this study, we performed a series of phenotypic and molecular assays using physiologically relevant in vitro and in vivo models to compare the oncogenicity of V1 with that of the prototype and other common natural variants. Through activation of AKT and K-Ras/ERK signalling pathways, V1 consistently showed greater oncogenicity compared with prototype and other variants, as demonstrated by increased cell proliferation, migration and invasion, as well as induction of larger tumours in athymic nude mice. This study complements our previous epidemiological and molecular observations pinpointing the higher oncogenicity of V1 compared with prototype and all other common variants. Since V1 is more commonly found in Eastern Asia, our report provides insight into the design of HPV-screening assays and selection of components for HPV vaccines in this region.IMPORTANCE Epidemiological studies have revealed that a wild type variant of HPV58 carrying an E7 variation, T20I/G63S (V1), is associated with a higher risk of cervical cancer. We previously reported that this increased oncogenicity could be the result of its greater ability to degrade pRB, thereby leading to an increased ability to grow in an anchorage-independent manner. In addition to this, this report further showed that this HPV variant induced activation of AKT and K-Ras/ERK signalling pathways, thereby, explaining its genuine oncogenicity in promoting cell proliferation, migration, invasion, and formation of tumours, all to a greater extent than prototype HPV58 and other common variants.

4.
J Infect ; 80(1): 84-98, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31580867

RESUMO

OBJECTIVE: To elucidate the effects of meteorological variations on the activity of influenza A and B in 11 sites across different climate regions. METHODS: Daily numbers of laboratory-confirmed influenza A and B cases from 2011-2015 were collected from study sites where the corresponding daily mean temperature, relative humidity, wind speed and daily precipitation amount were used for boosted regression trees analysis on the marginal associations and the interaction effects. RESULTS: Cold temperature was a major determinant that favored both influenza A and B in temperate and subtropical sites. Temperature-to-influenza A, but not influenza B, exhibited a U-shape association in subtropical and tropical sites. High relative humidity was also associated with influenza activities but was less consistent with influenza B activity. Compared with relative humidity, absolute humidity had a stronger association - it was negatively associated with influenza B activity in temperate zones, but was positively associated with both influenza A and B in subtropical and tropical zones. CONCLUSION: The association between meteorological factors and with influenza activity is virus type specific and climate dependent. The heavy influence of temperature on influenza activity across climate zones implies that global warming is likely to have an impact on the influenza burden.

5.
Gut ; 69(1): 83-91, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31611298

RESUMO

OBJECTIVE: The underlying microbial basis, predictors of therapeutic outcome and active constituent(s) of faecal microbiota transplantation (FMT) mediating benefit remain unknown. An international panel of experts presented key elements that will shape forthcoming FMT research and practice. DESIGN: Systematic search was performed, FMT literature was critically appraised and a 1-day round-table discussion was conducted to derive expert consensus on key issues in FMT research. RESULTS: 16 experts convened and discussed five questions regarding (1) the role of donor and recipient microbial (bacteria, viruses, fungi) parameters in FMT; (2) methods to assess microbiota alterations; (3) concept of keystone species and microbial predictors of FMT, (4) influence of recipient profile and antibiotics pretreatment on FMT engraftment and maintenance and (5) new developments in FMT formulations and delivery. The panel considered that variable outcomes of FMT relate to compositional and functional differences in recipient's microbiota, and likely donor-associated and recipient-associated physiological and genetic factors. Taxonomic composition of donor intestinal microbiota may influence the efficacy of FMT in recurrent Clostridioides difficile infections and UC. FMT not only alters bacteria composition but also establishes trans-kingdom equilibrium between gut fungi, viruses and bacteria to promote the recovery of microbial homeostasis. FMT is not a one size fits all and studies are required to identify microbial components that have specific effects in patients with different diseases. CONCLUSION: FMT requires optimisation before their therapeutic promise can be evaluated for different diseases. This summary will guide future directions and priorities in advancement of the science and practice of FMT.


Assuntos
Transplante de Microbiota Fecal/métodos , Antibacterianos/farmacologia , Clostridium difficile , Endoscopia Gastrointestinal , Enterocolite Pseudomembranosa/terapia , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Humanos , Doenças Inflamatórias Intestinais/terapia , Prognóstico , Recidiva , Doadores de Tecidos , Resultado do Tratamento
6.
Chem Res Toxicol ; 33(2): 470-481, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31874558

RESUMO

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is an important tobacco-specific nitrosamine (TSNA) that induces malignant tumors in rodents. High-risk human papillomavirus (hr-HPV) infection is an important cause of several human cancers. Epidemiological evidence has shown that HPV cooperatively induces carcinogenesis with tobacco smoke. In the present study, the synergistic carcinogenesis of NNK and HPV18 was investigated. Immortalized human esophageal epithelial SHEE cells containing the HPV18 E6E7 gene were constructed by lentiviral transfection. SHEE-E6E7 cells were exposed to NNK along with SHEE-V cells without HPV18 E6E7 as a negative control. The cooperation of NNK and HPV was examined by wound-healing, transwell, and colony-forming assays. The results showed that NNK exposure promoted the migration, invasion, and proliferation abilities of both SHEE-E6E7 and SHEE-V cells; however, the changes in these phenotypic features were remarkably stronger in SHEE-E6E7 cells than those in SHEE-V cells. Our findings indicate that NNK promotes malignant transformation of human esophageal epithelial cells and suggest a synergistic carcinogenesis with the HPV18 E6E7 oncogene. As reported previously, the formation of pyridyloxybutylated DNA adducts is a crucial step in NNK-mediated carcinogenesis. In order to clarify the influence of HPV on the formation of NNK-induced DNA adducts, the amounts of 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB)-releasing DNA adducts were determined using high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry. We observed that the levels of HPB-releasing adducts in SHEE-E6E7 cells were significantly higher (p < 0.01) than those of SHEE-V cells, which was in line with results of the phenotypic assays. In conclusion, this study provides direct evidence that NNK and HPV18 exhibit a synergistic effect on formation of DNA adducts, resulting in malignant transformation of esophageal epithelial cells. Such knowledge on the interaction between infection and smoking habits in the development of cancers informs cancer-prevention strategies. Further studies to delineate the molecular mechanism and to identify specific intervention targets are worthwhile.

7.
BMC Oral Health ; 19(1): 275, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806002

RESUMO

BACKGROUND: Microbial culture-based investigations of inflamed tonsil tissues have previously indicated enrichment of several microorganisms such as Streptococcus, Staphylococcus and Prevotella. These taxa were also largely reflected in DNA sequencing studies performed using tissue material. In comparison, less is known about the response of the overall oral cavity microbiota to acute tonsillitis despite their role in human health and evidence showing that their compositions are correlated with diseases such as oral cancers. In addition, the influence of subject-specific circumstances including consumption of prescription antibiotics and smoking habits on the microbiology of acute tonsillitis is unknown. METHODS: We collected oral rinse samples from 43 individuals admitted into hospital for acute tonsillitis and 165 non-disease volunteers recruited from the public, and compared their microbial community compositions using 16S rRNA gene sequencing. We assessed the impact of tonsillitis, whether subjects were prescribed antibiotics, the presence of oral abscesses and their smoking habits on community composition, and identified specific microbial taxa associated with tonsillitis and smoking. RESULTS: Oral rinse community composition was primarily associated with disease state (tonsillitis vs non-tonsillitis) although its effect was subtle, followed by smoking habit. Multiple Prevotella taxa were enriched in tonsillitis subjects compared to the non-tonsillitis cohort, whereas the non-tonsillitis cohort primarily showed associations with several Neisseria sequence variants. The presence of oral abscesses did not significantly influence community composition. Antibiotics were prescribed to a subset of individuals in the tonsillitis cohort but we did not observe differences in community composition associated with antibiotics consumption. In both tonsillitis and non-tonsillitis cohorts, smoking habit was associated with enrichment of several Fusobacterium variants. CONCLUSIONS: These findings show that the oral cavity microbial community is altered during acute tonsillitis, with a consistent enrichment of Prevotella during tonsillitis raising the possibility of targeted interventions. It also supports the possible link between smoking, Fusobacteria and oral cancers.

8.
BMC Cancer ; 19(1): 1211, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31830929

RESUMO

BACKGROUND: Increasing evidence indicates an etiological role of human papillomavirus (HPV) in head and neck cancers, particularly oropharyngeal squamous cell carcinoma (OPSCC). However, the association between HPV and other cancers, including esophageal and tongue remains unclear. This study delineated the molecular characteristics of HPV18 E6 and E7 in esophageal (EC109 and EC9706) and tongue (Tca83) cancer cell lines with reference to cervical cancer (HeLa). METHODS: We analysed the HPV transcription profiles of esophageal and tongue cancer cells through Next-generation RNA sequencing, and the role of HPV18 E6 and E7 in these cells was assessed via siRNA approach, Western blotting and immunofluorescence assays. RESULTS: Overall, the HPV transcription profiles of esophageal and tongue cancer cells mimicked that of cervical cancer cells, with notable disruption of E2, and expression of E6, spliced E6 (E6*), E7, E1 and L1 transcripts. As with cervical cancer cells, p53 and its downstream transactivation target, p21, were found to be the major targets of E6 in esophageal and tongue cancer cell lines. Intriguingly, E7 preferentially targeted p130 in the two esophageal cancer cell lines, instead of pRb as in cervical cancer. Tca83 exhibited an E7 to E6 transcript ratio comparable to HeLa (cervix), targeted the ERK1/2 and MMP2 pathways, and was dependent on E6 and E7 to survive and proliferate. In contrast, both the esophageal cancer cell lines were distinct from HeLa in these aspects. CONCLUSIONS: This is the first study that delineates transcript expression and protein interaction of HPV18 E6 and E7 in esophageal and tongue cancer cell lines, suggesting that HPV plays a role in inducing these cancers, albeit via distinct pathways than those observed in cervical cancer.

9.
BMC Public Health ; 19(1): 1514, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718611

RESUMO

BACKGROUND: Cervical cancer was the fourth most common cancer among women worldwide in 2012 and was the eighth most common cancer in 2014 and the eighth greatest cause of female cancer deaths in Hong Kong in 2015. Human papillomavirus (HPV) vaccination has been clinically documented to have a high efficacy in reducing HPV-related cervical intraepithelial neoplasia incidence. Therefore, receiving vaccination is a crucial public health measure to reduce disease burden. Significant others, such as schools and schoolteachers, have prominent influence in shaping adolescents' health perceptions and behavior. Therefore, the perspective of schools and schoolteachers regarding vaccination can significantly influence students' acceptance and accessibility of the vaccine. However, few studies have analyzed the perceptions of schoolteachers toward HPV vaccination, and even fewer have concerned how schoolteachers' perceptions influence their schools' motivation in implementing school-based HPV vaccination programs. This study was thus conducted to fill this literature gap. METHODS: With a Chinese community as the field site of this study, a qualitative approach of five focus group interviews was conducted with 35 schoolteachers from five primary and eight secondary schools in Hong Kong between July 2014 and January 2015. Thematic content analysis was used for data analysis. RESULTS: Perceptual, institutional, student and parental, and collaborator barriers interacted to discourage the sampled schoolteachers from organizing school-based HPV vaccination programs. Lack of knowledge regarding HPV vaccination, perception of HPV vaccination as inappropriate given the students' age, violation of traditional cultural values, lack of perceived needs and perceived risk, opposition from schools, low priority of HPV vaccination over other health education topics, lack of government support, lack of interest from parents and students, and lack of confidence in implementing organizations, all were the mentioned barriers. CONCLUSIONS: The sampled schoolteachers were demotivated to organize school-based HPV vaccination programs because of their perceptions and various social and cultural factors. As significant influencers of adolescent students, schoolteachers and schools should receive more support and information on organizing school-based HPV vaccination programs in the future.


Assuntos
Neoplasia Intraepitelial Cervical/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Papillomaviridae , Infecções por Papillomavirus/prevenção & controle , Professores Escolares , Instituições Acadêmicas , Neoplasias do Colo do Útero/prevenção & controle , Adolescente , Neoplasia Intraepitelial Cervical/virologia , Criança , Feminino , Educação em Saúde , Hong Kong/epidemiologia , Humanos , Programas de Imunização , Masculino , Motivação , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus , Pais , Aceitação pelo Paciente de Cuidados de Saúde , Pesquisa Qualitativa , Serviços de Saúde Escolar , Estudantes , Neoplasias do Colo do Útero/virologia , Vacinação , Adulto Jovem
10.
Aliment Pharmacol Ther ; 50(11-12): 1159-1171, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31648369

RESUMO

BACKGROUND: Emerging data suggest that alterations in gut fungi may be associated with the pathogenesis of inflammatory bowel disease (IBD). In healthy individuals, gut commensal fungi act synergistically with other members of the microbiota to maintain homeostasis but their role in IBD is less clear. AIM: To review the role of gut fungi and their trans-kingdom interactions with bacteria in IBD METHODS: A literature search was conducted on Ovid and Pubmed to select relevant animal and human studies that have reported fungi and IBD. RESULTS: There is an increased total fungal load particularly of Candida and Malassezia species in the faeces and mucosa of Crohn's disease patients, and a lower fungal diversity in the faeces of ulcerative colitis patients. Caspase recruitment domain-containing protein (CARD)-9 polymorphism in Crohn's disease patients favours Malassezia colonisation that worsens gut inflammation. Diet high in carbohydrates increased the total abundance of Candida species, whereas protein-rich diet had the opposite effect. Anti-fungal therapies are mostly used to treat Candida albicans or Histoplasma capsulatum infections in IBD, whereas pilot studies of supplementing fungal probiotics Saccharomycopsis fibuligera, Saccharomyces boulardii and Saccharomyces cerevisiae CNCM I-3856 strain showed therapeutic effects in IBD. CONCLUSIONS: Gut fungi are altered in patients with Crohn's disease and ulcerative colitis. Modulation of the fungal microbiota can be considered as a therapeutic approach for IBD. Future research should focus on understanding how the fungal microbiota interacts with other components of the gut microbiota in association with the pathogenesis and development of IBD.

11.
Front Microbiol ; 10: 2093, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552003

RESUMO

Given high genetic diversity of papillomaviruses (PV) and complex scenario of virus-host interaction, the genetic basis underlying the mechanisms of HPV carcinogenicity is not well understood. In an effort to evaluate the origin and evolution of PV pathogenicity, we collected paired oral, perianal, and genital swabs from a wild macaque population. Of the 117 surveyed macaques, 88 (75.2%) were positive for PV DNA in one or more sites, mostly common from genital swabs, followed by oral and perianal sites. All putative macaque PV types phylogenetically clustered into the genera Alpha-, Beta-, and Gammapapillomavirus, with a strong phylogeny-tropism association as observed in HPVs. Using a Bayesian Markov Chain Monte Carlo framework, we demonstrated ancient intra-host divergence of primate PVs in which multiple ancestors had split and adapted to specific host ecosystems at least 41 million years ago, prior to the speciation events of primate host species. Following subsequent divergence and niche adaptation, distinct but phylogenetically related PV types were transmitted to similar host ecosystems by closely related host animals when host speciation occurred, which may explain in part the origin of carcinogenicity of HPV type 16 (HPV16) and Macaca fascicularis PV type 3 (MfPV3) that evolved from a most recent common ancestor containing the determinants for cervicovaginal colonization and cervical cancer. The findings identifying evolutionary and biological relatedness between human and non-human primate PVs lay a genetic foundation for research on parasite-host interactions and carcinogenic outcomes, which will prove useful in further study of viral pathogenesis and host specificity. STUDY IMPORTANCE: To better understand the origin and evolution of PV carcinogenicity associated with cervical cancer, we applied a combination of phylogenetic and bioinformatic analyses to investigate the genetic diversity of macaque papillomaviruses, and estimate divergence times of human and non-human primate PVs. The majority of both human and non-human primate PVs cluster into α-, ß-, and γ-PVs, sharing similar evolutionary histories and biological properties to each other. The strong phylogeny-tropism association of primate PVs indicates an important role of niche adaptation and virus-host codivergence shaping the diversity of viral genomics, host specificity, immune exposure, and pathogenic property. Understanding the evolution of the family Papilloamviridae in general and the primate papillomaviruses in specific in relevant to virus-host interactions should provide important implications for viral pathogenesis and disease prevention.

12.
Emerg Infect Dis ; 25(9): 1730-1735, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31441758

RESUMO

Tools to detect human norovirus infectivity have been lacking. Using human intestinal enteroid cultures inoculated with GII.Pe-GII.4 Sydney-infected fecal samples, we determined that a real-time reverse transcription PCR cycle threshold cutoff of 30 may indicate infectious norovirus. This finding could be used to help guide infection control.


Assuntos
Infecções por Caliciviridae/epidemiologia , Norovirus/isolamento & purificação , Idoso , Infecções por Caliciviridae/virologia , China/epidemiologia , Fezes/virologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Norovirus/genética , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
13.
Gut ; 68(7): 1169-1179, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30842211

RESUMO

OBJECTIVE: The pathogenesis of UC relates to gut microbiota dysbiosis. We postulate that alterations in the viral community populating the intestinal mucosa play an important role in UC pathogenesis. This study aims to characterise the mucosal virome and their functions in health and UC. DESIGN: Deep metagenomics sequencing of virus-like particle preparations and bacterial 16S rRNA sequencing were performed on the rectal mucosa of 167 subjects from three different geographical regions in China (UC=91; healthy controls=76). Virome and bacteriome alterations in UC mucosa were assessed and correlated with patient metadata. We applied partition around medoids clustering algorithm and classified mucosa viral communities into two clusters, referred to as mucosal virome metacommunities 1 and 2. RESULTS: In UC, there was an expansion of mucosa viruses, particularly Caudovirales bacteriophages, and a decrease in mucosa Caudovirales diversity, richness and evenness compared with healthy controls. Altered mucosal virome correlated with intestinal inflammation. Interindividual dissimilarity between mucosal viromes was higher in UC than controls. Escherichia phage and Enterobacteria phage were more abundant in the mucosa of UC than controls. Compared with metacommunity 1, metacommunity 2 was predominated by UC subjects and displayed a significant loss of various viral species. Patients with UC showed substantial abrogation of diverse viral functions, whereas multiple viral functions, particularly functions of bacteriophages associated with host bacteria fitness and pathogenicity, were markedly enriched in UC mucosa. Intensive transkingdom correlations between mucosa viruses and bacteria were significantly depleted in UC. CONCLUSION: We demonstrated for the first time that UC is characterised by substantial alterations of the mucosa virobiota with functional distortion. Enrichment of Caudovirales bacteriophages, increased phage/bacteria virulence functions and loss of viral-bacterial correlations in the UC mucosa highlight that mucosal virome may play an important role in UC pathogenesis.


Assuntos
Colite Ulcerativa/virologia , Disbiose/virologia , Microbioma Gastrointestinal , Mucosa Intestinal/virologia , Reto/virologia , Adulto , Estudos de Casos e Controles , China , Colite Ulcerativa/patologia , Disbiose/patologia , Feminino , Humanos , Masculino , Reto/patologia
14.
mSystems ; 4(1)2019.
Artigo em Inglês | MEDLINE | ID: mdl-30834331

RESUMO

Proper preservation of stool samples to minimize microbial community shifts and inactivate infectious agents is important for self-collected specimens requiring shipment to laboratories when cold chain transport is not feasible. In this study, we evaluated the performance of six preservation solutions (Norgen, OMNI, RNAlater, CURNA, HEMA, and Shield) for these aspects. Following storage of human stool samples with these preservatives at room temperature for 7 days, three hypervariable regions of the bacterial 16S rRNA gene (V1-V2, V3-V4, and V4) were amplicon sequenced. We found that samples collected in two preservatives, Norgen and OMNI, showed the least shift in community composition relative to -80°C standards compared with other storage conditions, and both efficiently inhibited the growth of aerobic and anaerobic bacteria. RNAlater did not prevent bacterial activity and exhibited relatively larger community shift. Although the effect of preservation solution was small compared to intersubject variation, notable changes in microbiota composition were observed, which could create biases in downstream data analysis. When community profiles inferred from different 16S rRNA gene hypervariable regions were compared, we found differential sensitivity of primer sets in identifying overall microbial community and certain bacterial taxa. For example, reads generated by the V4 primer pair showed a higher alpha diversity of the gut microbial community. The degenerate 27f-YM primer failed to detect the majority of Bifidobacteriales. Our data indicate that choice of preservation solution and 16S rRNA gene primer pair are critical determinants affecting gut microbiota profiling. IMPORTANCE Large-scale human microbiota studies require specimens collected from multiple sites and/or time points to maximize detection of the small effects in microbe-host interactions. However, batch biases caused by experimental protocols, such as sample collection, massively parallel sequencing, and bioinformatics analyses, remain critical and should be minimized. This work evaluated the effects of preservation solutions and bacterial 16S rRNA gene primer pairs in revealing human gut microbiota composition. Since notable changes in detecting bacterial composition and abundance were observed among choice of preservatives and primer pairs, a consistent methodology is essential in minimizing their effects to facilitate comparisons between data sets.

15.
J Clin Virol ; 114: 32-36, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30913520

RESUMO

BACKGROUND: A blood test to serve as a tumor marker for cervical cancer would be useful to clinicians to guide treatment and provide an early signal for recurrence. The development of droplet digital PCR has enabled the detection of HPV DNA in patient serum, providing a potential marker for cervical cancer. OBJECTIVES: To report on a blood-based test for HPV-specific E7 and L1 genes, which may serve as a tumor marker to guide treatment and detect early recurrence in cervical cancer. STUDY DESIGN: Pre-treatment plasma samples were investigated from 138 Hong Kong Chinese women with primary invasive squamous cell carcinoma and adenocarcinoma of the cervix with tumor samples expressing HPV16 or HPV18. Two genes specific to the human papillomavirus, E7 and L1, were measured in cell free DNA (cfDNA) extracted from plasma using droplet digital PCR. Analysis of detectable E7 and L1 levels was performed to investigate the potential of liquid biopsy of E7 and L1 as a clinically useful molecular biomarker. RESULTS: The majority of patients had HPV16 (71.7%), squamous cell carcinoma (78.3%) and stage IB-II disease (82.6%). HPV E7 and L1 sequences were detected in plasma cfDNA from 61.6% (85/138) of patients. Patients with high viral load (defined as ≥20 E7 or L1 copies per 20 µL reaction volume) had increased risk of recurrence and death at 5 years on univariate analysis but not multivariate analysis. CONCLUSIONS: HPV DNA can be quantitatively detected with the use of cfDNA. This has the potential to provide a clinically useful tumor marker for patients with cervical cancer that can aid in post-treatment surveillance and estimating the risk of disease relapse.

16.
BMC Cancer ; 19(1): 138, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744599

RESUMO

BACKGROUND: Human papillomavirus (HPV) is an etiological agent of cervical cancer. Yet co-factors are believed to be involved in HPV-mediated carcinogenesis. Polycyclic aromatic hydrocarbons (PAHs) are considered as one of these co-factors. Epidemiologic studies have associated high PAH exposure with increased risk for cancer development. To date, many studies focus on benzo[a]pyrene, however, the role of other PAHs should not be neglected. This study aimed to compare the potential of different PAHs as a co-factor in HPV-mediated carcinogenesis, and to investigate the possible mechanisms involved. METHODS: The effect of 17 PAHs on high-risk HPV (HPV16) were examined in this study. HPV16 E7 oncogene was expressed in primary cells extracted from baby rat kidney and treated with PAHs. The co-transforming ability of PAHs were measured by colony formation index according to the number and size of transformed colonies. Effects of PAHs on proliferation of HPV-null (C33A) and -infected (CaSki) were examined using CCK-8 assay. Wound healing assay and matrigel invasion chambers were used to investigate effects of PAHs on cell motility and invasivion of HPV-null (MCF7, C33A) and -infected (SiHa) cells. RESULTS: Benzo[a]pyrene (BaP), dibenz[a,h]anthracene (DBA) and indeno[1,2,3-cd]pyrene (IDP) showed the greatest co-transforming potential in the baby rat kidney cell system. Short-term exposure to BaP, DBA, IDP and pyrene (PR) did not affect proliferation of C33A or CaSki cells, however, long-term exposure of these four PAHs led to dramatic increase in growth rate of CaSki cells by 120-140%. Besides, exposure of PAHs has an effect on cell motility and invasiveness of C33A and SiHa cells, but not for MCF7 cells. Exposure of BaP and DBA enhanced migration (1.26 to 1.40-fold) and invasion (1.68 to 1.94-fold) capacity of C33A cells. Intriguingly, exposure of all four types of PAHs boosted the migration (1.12 to 1.28-fold) and invasion (1.26 to 1.40-fold) capacity of SiHa cells. CONCLUSIONS: Our results indicate that exposure to PAHs can be a key co-factor in HPV-related cancer development. They could act on all three stages, namely initiation, promotion and progression. Further study is needed to unveil the mechanisms by which PAHs interact with HPV to cause malignancy.


Assuntos
Cocarcinogênese , Neoplasias/etiologia , Papillomaviridae , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Viral , Humanos , Papillomaviridae/fisiologia , Proteínas E7 de Papillomavirus/genética
17.
Aliment Pharmacol Ther ; 49(4): 354-363, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30628108

RESUMO

BACKGROUND: Faecal microbiota transplantation (FMT) is effective for Clostridium difficile infections (CDI) refractory to standard treatment and is being studied in other diseases. AIM: To evaluate donor characteristics, procedures and clinical outcomes of FMT. METHODS: We systematically reviewed FMT studies published up to 29 August 2018 using MEDLINE (R) and EMBASE and identified clinical studies with FMT donor information. We reported data on donor characteristics, screening criteria, administration, clinical outcomes and adverse events. RESULTS: Among 5267 reports, 239 full-text articles were screened and 168 articles were included. FMT was performed commonly for CDI (n = 108) and inflammatory bowel disease (IBD) (n = 31). We reported characteristics of 1513 donors [58% male; mean age, 34.3 years; mean body mass index, 21.6]. Donors in Asia were younger than the West (mean age 30.7 vs 32.9, P = 0.00075). Less than 50% of studies screened donors for transmittable pathogens. Final cure rate for CDI was 95.6% (95% confidence interval [CI], 93.9%-97.1%) and final remission rates for ulcerative colitis (UC) and Crohn's disease (CD) were 39.6% (95% CI, 25.4%-54.6%) and 47.5% (95% CI, 29.4%-65.8%), respectively. Cure rates in CDI and final remission rates for CD and UC were comparable across all routes of FMT administration. Overall adverse event incidence was <1%, mostly GI-related. Adverse event rates did not differ significantly between routes of FMT administration or indication. CONCLUSIONS: In a systematic review assessing donor characteristics and FMT efficacy, we observed heterogeneity in donor selection, application and outcomes of FMT. These data can facilitate standardisation of FMT protocols for various diseases.


Assuntos
Infecções por Clostridium/terapia , Transplante de Microbiota Fecal/métodos , Doenças Inflamatórias Intestinais/terapia , Adulto , Índice de Massa Corporal , Colite Ulcerativa/terapia , Doença de Crohn/etiologia , Feminino , Humanos , Masculino , Programas de Rastreamento , Doadores de Tecidos/estatística & dados numéricos
18.
PeerJ ; 7: e6172, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30648014

RESUMO

Stools are commonly used as proxies for studying human gut microbial communities as sample collection is straightforward, cheap and non-invasive. In large-scale human population surveys, however, sample integrity becomes an issue as it is not logistically feasible for researchers to personally collect stools from every participant. Instead, participants are usually given guidelines on sample packaging and storage, and asked to deliver their stools to a centralised facility. Here, we tested a number of delivery conditions (temperature, duration and addition of preservative medium) and assessed their effects on stool microbial community composition using 16S rRNA gene amplicon sequencing. The largest source of variability in stool community composition was attributable to inter-individual differences regardless of delivery condition. Although the relative effect of delivery condition on community composition was small compared to inter-individual variability (1.6% vs. 60.5%, permutational multivariate analysis of variance [PERMANOVA]) and temporal variation within subjects over 10 weeks (5.2%), shifts in microbial taxa associated with delivery conditions were non-systematic and subject-specific. These findings indicated that it is not possible to model or accurately predict shifts in stool community composition associated with sampling logistics. Based on our findings, we recommend delivery of fresh, preservative-free stool samples to laboratories within 2 hr either at ambient or chilled temperatures to minimise perturbations to microbial community composition. In addition, subsamples from different fractions of the same stool displayed a small (3.3% vs. 72.6% inter-individual variation, PERMANOVA) but significant effect on community composition. Collection of larger sample volumes for homogenisation is recommended.

20.
J Virol Methods ; 265: 35-41, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30562608

RESUMO

Dengue fever is a mosquito-borne viral disease with dramatically increasing morbidity rate worldwide in decades. Since there is no specific treatment to date, early diagnosis is important for providing proper timely medical care to minimize mortality, and for the prompt initiation of public health control measures. NS5 is a potential biomarker for dengue virus infection due to its highly conserved and immunogenic properties. In this study, the DENV 2 NS5 full-length and the DENV 2 NS5 C-terminus RNA-dependent RNA polymerase domain fragment (NS5-C70) expression plasmids were constructed, and the 104 kDa full-length NS5 and the 70 kDa NS5-C70 were respectively expressed in Escherichia coli. These two purified recombinant products were found to react with the sera of patients infected with dengue virus when analyzed by an enzyme-linked immunosorbent assay (ELISA), which resulted in significantly higher absorption values than those of control sera. The recombinant DENV 2 NS5 exhibited strong reactivity to each of the four types of sera, whereas the NS5-C70 showed strong reactivity only to DENV 2 and 4. In comparison, the positive agreement value of recombinant NS5-based assay with either MyBioSource or Panbio assay was higher than that of the two commercially available IgG indirect ELISA kits. These results suggest that the recombinant DENV 2 NS5 be an effective antigen for detection of dengue virus infection. The recombinant NS5-C70 may also be used as an auxiliary antigen for diagnostic purposes.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Dengue/diagnóstico , Proteínas Recombinantes/imunologia , Testes Sorológicos/métodos , Proteínas não Estruturais Virais/imunologia , Antígenos Virais/genética , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Humanos , Proteínas Recombinantes/genética , Sensibilidade e Especificidade , Proteínas não Estruturais Virais/genética
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