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1.
Mol Cancer ; 22(1): 206, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38093346

RESUMO

BACKGROUND: Social behaviors such as altruism, where one self-sacrifices for collective benefits, critically influence an organism's survival and responses to the environment. Such behaviors are widely exemplified in nature but have been underexplored in cancer cells which are conventionally seen as selfish competitive players. This multidisciplinary study explores altruism and its mechanism in breast cancer cells and its contribution to chemoresistance. METHODS: MicroRNA profiling was performed on circulating tumor cells collected from the blood of treated breast cancer patients. Cancer cell lines ectopically expressing candidate miRNA were used in co-culture experiments and treated with docetaxel. Ecological parameters like relative survival and relative fitness were assessed using flow cytometry. Functional studies and characterization performed in vitro and in vivo include proliferation, iTRAQ-mass spectrometry, RNA sequencing, inhibition by small molecules and antibodies, siRNA knockdown, CRISPR/dCas9 inhibition and fluorescence imaging of promoter reporter-expressing cells. Mathematical modeling based on evolutionary game theory was performed to simulate spatial organization of cancer cells. RESULTS: Opposing cancer processes underlie altruism: an oncogenic process involving secretion of IGFBP2 and CCL28 by the altruists to induce survival benefits in neighboring cells under taxane exposure, and a self-sacrificial tumor suppressive process impeding proliferation of altruists via cell cycle arrest. Both processes are regulated concurrently in the altruists by miR-125b, via differential NF-κB signaling specifically through IKKß. Altruistic cells persist in the tumor despite their self-sacrifice, as they can regenerate epigenetically from non-altruists via a KLF2/PCAF-mediated mechanism. The altruists maintain a sparse spatial organization by inhibiting surrounding cells from adopting the altruistic fate via a lateral inhibition mechanism involving a GAB1-PI3K-AKT-miR-125b signaling circuit. CONCLUSIONS: Our data reveal molecular mechanisms underlying manifestation, persistence and spatial spread of cancer cell altruism. A minor population behave altruistically at a cost to itself producing a collective benefit for the tumor, suggesting tumors to be dynamic social systems governed by the same rules of cooperation in social organisms. Understanding cancer cell altruism may lead to more holistic models of tumor evolution and drug response, as well as therapeutic paradigms that account for social interactions. Cancer cells constitute tractable experimental models for fields beyond oncology, like evolutionary ecology and game theory.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , Altruísmo , Fosfatidilinositol 3-Quinases , MicroRNAs/genética , Neoplasias da Mama/genética
2.
Proc Natl Acad Sci U S A ; 117(1): 619-628, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31843889

RESUMO

Influenza B viruses have circulated in humans for over 80 y, causing a significant disease burden. Two antigenically distinct lineages ("B/Victoria/2/87-like" and "B/Yamagata/16/88-like," termed Victoria and Yamagata) emerged in the 1970s and have cocirculated since 2001. Since 2015 both lineages have shown unusually high levels of epidemic activity, the reasons for which are unclear. By analyzing over 12,000 influenza B virus genomes, we describe the processes enabling the long-term success and recent resurgence of epidemics due to influenza B virus. We show that following prolonged diversification, both lineages underwent selective sweeps across the genome and have subsequently taken alternate evolutionary trajectories to exhibit epidemic dominance, with no reassortment between lineages. Hemagglutinin deletion variants emerged concomitantly in multiple Victoria virus clades and persisted through epistatic mutations and interclade reassortment-a phenomenon previously only observed in the 1970s when Victoria and Yamagata lineages emerged. For Yamagata viruses, antigenic drift of neuraminidase was a major driver of epidemic activity, indicating that neuraminidase-based vaccines and cross-reactivity assays should be employed to monitor and develop robust protection against influenza B morbidity and mortality. Overall, we show that long-term diversification and infrequent selective sweeps, coupled with the reemergence of hemagglutinin deletion variants and antigenic drift of neuraminidase, are factors that contributed to successful circulation of diverse influenza B clades. Further divergence of hemagglutinin variants with poor cross-reactivity could potentially lead to circulation of 3 or more distinct influenza B viruses, further complicating influenza vaccine formulation and highlighting the urgent need for universal influenza vaccines.


Assuntos
Doenças Transmissíveis Emergentes/virologia , Epidemias/prevenção & controle , Evolução Molecular , Vírus da Influenza B/genética , Vacinas contra Influenza/uso terapêutico , Influenza Humana/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/imunologia , Doenças Transmissíveis Emergentes/prevenção & controle , Variação Genética , Genoma Viral/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza B/imunologia , Vírus da Influenza B/patogenicidade , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Neuraminidase/genética , Neuraminidase/imunologia , Seleção Genética/imunologia
3.
J Couns Psychol ; 70(2): 159-171, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36455023

RESUMO

Group climate is an important factor in group counseling and psychotherapy process and outcome research. The current investigation examined group climate changes (from early to late sessions) at the within-group (i.e., group members) and between-group (i.e., group-as-a-whole) levels in predicting changes in group members' emotional cultivation in group counseling. A total of 236 Taiwanese children and adolescents across 41 groups participated in this study. Members' ratings of group climate (i.e., engagement and conflict) were partitioned into within-group and between-group components, and polynomial regression with response surface analysis was used to examine the association between changes in group engagement and conflict (at the member- and group-level) from early to late group sessions on changes in emotional cultivation. Results supported the theoretical hypothesis that when a group-as-a-whole reported increasing engagement from early to late group sessions, relative to other groups (i.e., between-group effect), members of that group experienced greater growth in emotional cultivation. Results also indicated that group members reported greater growth in emotional cultivation when there was consistent and high engagement or consistent and low conflict from early to late group sessions. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Aconselhamento , Emoções , Adolescente , Criança , Humanos , Apego ao Objeto , Inquéritos e Questionários
5.
J Couns Psychol ; 69(5): 711-721, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35549277

RESUMO

Theoretically, group leaders can play a significant role in contributing to the effectiveness of group counseling intervention. However, very few studies have examined the group leader's effects on the client-rated group counseling outcomes. We hypothesized that responsive group leaders who were caring, understanding, and respectful could serve as safe havens and secure bases to facilitate their group members' social and emotional cultivation. The current investigation examined the effects of leader responsiveness on group members' social-emotional cultivation (SEC). A total of 307 Taiwanese children and adolescent clients across 53 groups participated in an eight-session emotional cultivation group intervention. There were five time points of data collection (i.e., preintervention, third group session, sixth group session, postintervention, and a 4-week follow-up), and the variance partitioning method was used to partition longitudinal data into within-member, within-group, and between-group variance components. The results of hierarchical linear modeling revealed that the group leader's responsiveness significantly predicted group members' SEC at each of the three levels of analysis: Individual members had greater change in SEC when (a) they perceived higher leader responsiveness in a time period compared to the average rating of leader responsiveness across all time periods, (b) they perceived higher leader responsiveness compared to the average rating of leader responsiveness across all members in the same group, and (c) the group-as-a-whole perceived higher leader responsiveness than the average rating of leader responsiveness across all groups. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Emoções , Liderança , Adolescente , Criança , Aconselhamento , Humanos
6.
Indoor Air ; 31(6): 2281-2295, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34138487

RESUMO

The incidence of several respiratory viral infections has been shown to be related to climate. Because humans spend most of their time indoors, measures of indoor climate, rather than outdoor climate, may be better predictors of disease incidence and transmission. Therefore, understanding the relationship between indoor and outdoor climate will help illuminate their influence on the seasonality of diseases caused by respiratory viruses. Indoor-outdoor relationships between temperature and humidity have been documented in temperate regions, but little information is available for tropical regions, where seasonal patterns of respiratory viral diseases differ. We have examined indoor-outdoor correlations of temperature, relative humidity (RH), and absolute humidity (AH) over a 1-year period in each of seven tropical cities. Across all cities, the average monthly indoor temperature was 25 ± 3°C (mean ± standard deviation) with a range of 20-30°C. The average monthly indoor RH was 66 ± 9% with a range of 50-78%, and the average monthly indoor AH was 15 ± 3 g/m3 with a range of 10-23 g/m3 . Indoor AH and RH were linearly correlated with outdoor AH when the air conditioning (AC) was off, suggesting that outdoor AH may be a good proxy of indoor humidity in the absence of AC. All indoor measurements were more strongly correlated with outdoor measurements as distance from the equator increased. Such correlations were weaker during the wet season, especially when AC was in operation. These correlations will provide insight for assessing the seasonality of respiratory viral infections using outdoor climate data, which is more widely available than indoor data, even though transmission of these diseases mainly occurs indoors.


Assuntos
Poluição do Ar em Ambientes Fechados , Umidade , Temperatura , Clima Tropical , Estações do Ano
8.
J Couns Psychol ; 66(4): 409-423, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30985169

RESUMO

Research on emotion regulation in East Asian children and adolescents is limited. One obstacle hindering the development of emotion regulation for East Asian children and adolescents is the lack of a culturally sensitive measure. To fill this gap, we have developed and validated the Emotional Cultivation Scale using samples of Taiwanese children and adolescents. In Study 1, an exploratory factor analysis (n = 341) identified two factors: Cultivating Emotion Strategies and Understanding Emotion Connotations. A confirmatory factor analysis (n = 358) confirmed this two-factor structure. Coefficient αs were .69 to .88 for Emotional Cultivation. Convergent validity was evidenced by positive associations with cognitive reappraisal and cognitive flexibility. Discriminant validity was supported by a nonsignificant association with suppression. Concurrent validity was revealed by positive associations with positive affect, basic psychological need satisfaction, gratitude, responsiveness from teachers, responsiveness from parents, and academic self-efficacy. Incremental validity was evidenced by the finding that emotional cultivation significantly accounted for an additional 2 to 20% of the variance in predicting cognitive flexibility, positive affect, basic psychological need satisfaction, gratitude, responsiveness from teachers, responsiveness from parents, and academic self-efficacy above and beyond cognitive reappraisal and suppression. Results from the multigroup analysis further indicated factor loading invariance and validity invariance between boys and girls and between elementary and middle schools. The factor structure was cross-validated by a clinical sample of Taiwanese children and adolescents (N = 161) and their parents in Study 2 (N = 159). The counseling implications were discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Povo Asiático/psicologia , Emoções , Adolescente , Adulto , Idoso , Cuidadores/psicologia , Criança , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pais/psicologia , Reprodutibilidade dos Testes , Instituições Acadêmicas , Adulto Jovem
9.
Clin Otolaryngol ; 44(2): 114-123, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30294871

RESUMO

OBJECTIVE: BRAF mutation is the commonest mutation seen in papillary thyroid cancer (PTC), but its prevalence and clinical significance vary across countries. We aim to evaluate the prevalence and clinico-pathological correlation of BRAF mutation in PTC patients at our centre. STUDY DESIGN: Retrospective cohort study of 75 consecutive archival thyroid specimens, whereby BRAF mutation was detected using a polymerase chain reaction (PCR) technique and correlated with clinical and pathological features and outcomes. SETTING: Tertiary university hospital in Singapore. PARTICIPANTS: A total of 75 consecutive histologically proven archival thyroid specimens from patients who underwent thyroidectomy for PTC were accrued for this study. MAIN OUTCOME MEASURES: Main outcome is to determine the prevalence of the BRAF mutation in our South-East Asian population. Secondary aim is to correlate the mutational status with adverse pathological features like histological variants, multi-focality, lymphovascular invasion and extra-thyroidal extension, clinical features like demographics, TNM stage, recurrence and survival, as well as treatment details like type of surgery performed and radioiodine doses. RESULTS: BRAF mutation was detected in 56% (42/75) of PTC. All but one BRAF-mutated PTC had the BRAFV600E mutation. BRAF-mutated tumours were associated with an advanced T-stage (P = 0.049) and were more likely to have a central neck dissection (P = 0.036). There was no significant correlation between BRAF mutation status and clinical outcomes. CONCLUSION: The prevalence of BRAF mutation is 56%. BRAF mutation-positive tumours were associated with locally advanced disease, but not poorer survival.


Assuntos
Povo Asiático/genética , Mutação/genética , Recidiva Local de Neoplasia/epidemiologia , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Singapura , Taxa de Sobrevida , Câncer Papilífero da Tireoide/mortalidade , Câncer Papilífero da Tireoide/terapia , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia , Adulto Jovem
10.
J Infect Dis ; 218(10): 1592-1601, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-29986093

RESUMO

Background: Varicella zoster virus (VZV) may cause encephalitis, both with and without rash. Here we investigate whether viruses recovered from the central nervous system (CNS; encephalitis or meningitis) differ genetically from those recovered from non-CNS samples. Methods: Enrichment-based deep sequencing of 45 VZV genomes from cerebral spinal fluid (CSF), plasma, bronchoalveolar lavage (BAL), and vesicles was carried out with samples collected from 34 patients with and without VZV infection of the CNS. Results: Viral sequences from multiple sites in the same patient were identical at the consensus level. Virus from vesicle fluid and CSF in cases of meningitis showed low-level diversity. By contrast, plasma, BAL, and encephalitis had higher numbers of variant alleles. Two CSF-encephalitis samples had high genetic diversity, with variant frequency patterns typical of mixed infections with different clades. Conclusions: Low viral genetic diversity in vesicle fluid is compatible with previous observations that VZV skin lesions arise from single or low numbers of virions. A similar result was observed in VZV from cases of VZV meningitis, a generally self-limiting infection. CSF from cases of encephalitis had higher diversity with evidence for mixed clade infections in 2 cases. We hypothesize that reactivation from multiple neurons may contribute to the pathogenesis of VZV encephalitis.


Assuntos
DNA Viral/líquido cefalorraquidiano , Encefalite por Varicela Zoster/virologia , Herpesvirus Humano 3/classificação , Herpesvirus Humano 3/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Coinfecção/virologia , Vesículas Citoplasmáticas/virologia , Variação Genética , Genoma Viral/genética , Humanos , Pessoa de Meia-Idade , Carga Viral , Adulto Jovem
11.
Hum Brain Mapp ; 39(7): 2742-2752, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29520911

RESUMO

We investigated the influence of the apolipoprotein E-ɛ4 allele (APOE-ɛ4) on longitudinal age-related changes in brain functional connectivity (FC) and cognition, in view of mixed cross-sectional findings. One hundred and twenty-two healthy older adults (aged 58-79; 25 APOE-ɛ4 carriers) underwent task-free fMRI scans at baseline. Seventy-eight (16 carriers) had at least one follow-up (every 2 years). Changes in intra- and internetwork FCs among the default mode (DMN), executive control (ECN), and salience (SN) networks, as well as cognition, were quantified using linear mixed models. Cross-sectionally, APOE-ɛ4 carriers had lower functional connectivity between the ECN and SN than noncarriers. Carriers also showed a stronger age-dependent decrease in visuospatial memory performance. Longitudinally, carriers had steeper increase in inter-ECN-DMN FC, indicating loss of functional segregation. The longitudinal change in processing speed performance was not moderated by APOE-ɛ4 genotype, but the brain-cognition association was. In younger elderly, faster loss of segregation was correlated with greater decline in processing speed regardless of genotype. In older elderly, such relation remained for noncarriers but reversed for carriers. APOE-ɛ4 may alter aging by accelerating the change in segregation between high-level cognitive systems. Its modulation on the longitudinal brain-cognition relationship was age-dependent.


Assuntos
Envelhecimento/fisiologia , Apolipoproteínas E/genética , Cognição/fisiologia , Conectoma/métodos , Rede Nervosa/fisiologia , Fatores Etários , Idoso , Envelhecimento/genética , Apolipoproteína E4/genética , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem
12.
J Med Virol ; 90(3): 485-489, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29073731

RESUMO

The Cepheid Xpert® Norovirus kit automates sample processing, nucleic acid extraction, and real-time reverse transcription polymerase chain reactions (RT-PCRs) to detect norovirus genogroups I (GI) and II (GII). Eighty-five stool samples collected between February 2015 and May 2017 were used to compare the performance of a user-modified Xpert assay against a clinically validated laboratory-developed test (LDT). Of the 85 samples, 54 were previously archived in -80°C freezer. The remaining 31 were fresh samples tested concurrently with the LDT. The results of all samples tested using the Xpert kit and LDT were found to be concordant, including 12 GI- and 42 GII-positive samples, 1 GI and GII coinfection, and 30 negative samples. Comparison of the assays showed perfect concordance with a kappa coefficient score of 1.00 (95%CI from 1.00 to 1.00). Of the 30 negative stool samples tested, three samples were positive for rotavirus detected using an immunochromatographic assay, with no cross-reactivity shown in both LDT and Xpert assays. In-run sample processing control of the Xpert assay for all negative samples tested showed no/minor inhibition. Compared to the LDT, the Xpert assay produced similar or better Ct values for detection. It also showed better mitigation of PCR inhibition in stool sample testing.


Assuntos
Infecções por Caliciviridae/diagnóstico , Norovirus/isolamento & purificação , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bancos de Espécimes Biológicos , Criança , Pré-Escolar , Técnicas de Laboratório Clínico/métodos , Reações Cruzadas , Fezes/virologia , Feminino , Gastroenterite/virologia , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Norovirus/genética , RNA Viral/isolamento & purificação , Sensibilidade e Especificidade , Adulto Jovem
13.
Clin Infect Dis ; 64(10): 1328-1334, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28199524

RESUMO

BACKGROUND: While evidence exists to support the effectiveness of neuraminidase inhibitors (NAIs) in reducing mortality when given to hospitalized patients with A(H1N1)pdm09 virus infection, the impact of outpatient treatment on hospitalization has not been clearly established. We investigated the impact of outpatient NAI treatment on subsequent hospitalization in patients with A(H1N1)pdm09 virus infection. METHODS: We assembled general community and outpatient data from 9 clinical centers in different countries collected between January 2009 and December 2010. We standardized data from each study center to create a pooled dataset and then used mixed-effects logistic regression modeling to determine the effect of NAI treatment on hospitalization. We adjusted for NAI treatment propensity and preadmission antibiotic use, including "study center" as a random intercept to account for differences in baseline hospitalization rate between centers. RESULTS: We included 3376 patients with influenza A(H1N1)pdm09, of whom 3085 (91.4%) had laboratory-confirmed infection. Eight hundred seventy-three patients (25.8%) received outpatient or community-based NAI treatment, 928 of 2395 (38.8%) with available data had dyspnea or respiratory distress, and hospitalizations occurred in 1705 (50.5%). After adjustment for preadmission antibiotics and NAI treatment propensity, preadmission NAI treatment was associated with decreased odds of hospital admission compared to no NAI treatment (adjusted odds ratio, 0.24; 95% confidence interval, 0.20-0.30). CONCLUSIONS: In a population with confirmed or suspected A(H1N1)pdm09 and at high risk of hospitalization, outpatient or community-based NAI treatment significantly reduced the likelihood of requiring hospital admission. These data suggest that community patients with severe influenza should receive NAI treatment.


Assuntos
Antivirais/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Neuraminidase/antagonistas & inibidores , Adolescente , Adulto , Idoso , Assistência Ambulatorial , Antibacterianos/uso terapêutico , Antivirais/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Feminino , Hospitalização , Humanos , Influenza Humana/diagnóstico , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pacientes Ambulatoriais , Análise de Regressão , Fatores de Risco , Adulto Jovem
14.
Clin Chem ; 63(3): 731-741, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28073899

RESUMO

BACKGROUND: Molecular characterization of circulating tumor cells (CTCs) holds great promise for monitoring metastatic progression and characterizing metastatic disease. However, leukocyte and red blood cell contamination of routinely isolated CTCs makes CTC-specific molecular characterization extremely challenging. METHODS: Here we report the use of a paper-based medium for efficient extraction of microRNAs (miRNAs) from limited amounts of biological samples such as rare CTCs harvested from cancer patient blood. Specifically, we devised a workflow involving the use of Flinders Technology Associates (FTA)® Elute Card with a digital PCR-inspired "partitioning" method to extract and purify miRNAs from plasma and CTCs. RESULTS: We demonstrated the sensitivity of this method to detect miRNA expression from as few as 3 cancer cells spiked into human blood. Using this method, background miRNA expression was excluded from contaminating blood cells, and CTC-specific miRNA expression profiles were derived from breast and colorectal cancer patients. Plasma separated out during purification of CTCs could likewise be processed using the same paper-based method for miRNA detection, thereby maximizing the amount of patient-specific information that can be derived from a single blood draw. CONCLUSIONS: Overall, this paper-based extraction method enables an efficient, cost-effective workflow for maximized recovery of small RNAs from limited biological samples for downstream molecular analyses.


Assuntos
Perfilação da Expressão Gênica/métodos , MicroRNAs/sangue , MicroRNAs/genética , Células Neoplásicas Circulantes/metabolismo , Papel , Humanos , MicroRNAs/análise , MicroRNAs/isolamento & purificação , Células Neoplásicas Circulantes/patologia , Células Tumorais Cultivadas
15.
J Virol ; 89(14): 7133-46, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25926648

RESUMO

UNLABELLED: Varicella-zoster virus (VZV) is a human herpesvirus, which during primary infection typically causes varicella (chicken pox) and establishes lifelong latency in sensory and autonomic ganglia. Later in life, the virus may reactivate to cause herpes zoster (HZ; also known as shingles). To prevent these diseases, a live-attenuated heterogeneous vaccine preparation, vOka, is used routinely in many countries worldwide. Recent studies of another alphaherpes virus, infectious laryngotracheitis virus, demonstrate that live-attenuated vaccine strains can recombine in vivo, creating virulent progeny. These findings raised concerns about using attenuated herpesvirus vaccines under conditions that favor recombination. To investigate whether VZV may undergo recombination, which is a prerequisite for VZV vaccination to create such conditions, we here analyzed 115 complete VZV genomes. Our results demonstrate that recombination occurs frequently for VZV. It thus seems that VZV is fully capable of recombination if given the opportunity, which may have important implications for continued VZV vaccination. Although no interclade vaccine wild-type recombinant strains were found, intraclade recombinants were frequently detected in clade 2, which harbors the vaccine strains, suggesting that the vaccine strains have already been involved in recombination events, either in vivo or in vitro during passages in cell culture. Finally, previous partial and complete genomic studies have described strains that do not cluster phylogenetically to any of the five established clades. The additional VZV strains sequenced here, in combination with those previously published, have enabled us to formally define a novel sixth VZV clade. IMPORTANCE: Although genetic recombination has been demonstrated to frequently occur for other human alphaherpesviruses, herpes simplex viruses 1 and 2, only a few ancient and isolated recent recombination events have hitherto been demonstrated for VZV. In the present study, we demonstrate that VZV also frequently undergoes genetic recombination, including strains belonging to the clade containing the vOKA strain.


Assuntos
Herpesvirus Humano 3/genética , Recombinação Genética , Adulto , Criança , Pré-Escolar , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Variação Genética , Genoma Viral , Herpesvirus Humano 3/isolamento & purificação , Humanos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência
16.
Respiration ; 92(5): 286-294, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27649510

RESUMO

BACKGROUND: Pathogens are often not identified in severe community-acquired pneumonia (CAP), and the few studies using polymerase chain reaction (PCR) techniques for virus detection are from temperate countries. OBJECTIVE: This study assesses if PCR amplification improves virus and bacteria detection, and if viral infection contributes to mortality in severe CAP in a tropical setting, where respiratory pathogens have less well-defined seasonality. METHODS: In this cohort study of patients with severe CAP in an intensive care unit, endotracheal aspirates for intubated patients and nasopharyngeal swabs for non-intubated patients were sent for PCR amplification for respiratory viruses. Blood, endotracheal aspirates for intubated patients, and sputum for non-intubated patients were analysed using a multiplex PCR system for bacteria. RESULTS: Out of 100 patients, using predominantly cultures, bacteria were identified in 42 patients; PCR amplification increased this number to 55 patients. PCR amplification identified viruses in 32 patients. In total, only bacteria, only viruses, and both bacteria and viruses were found in 37, 14, and 18 patients, respectively. The commonest viruses were influenza A H1N1/2009 and rhinovirus; the commonest bacterium was Streptococcus pneumoniae. Hospital mortality rates for patients with no pathogens, bacterial infection, viral infection, and bacterial-viral co-infection were 16.1, 24.3, 0, and 5.6%, respectively (p = 0.10). On multivariable analysis, virus detection was associated with lower mortality (adjusted odds ratio 0.12, 95% confidence interval 0.2-0.99; p = 0.049). CONCLUSIONS: Viruses and bacteria were detected in 7 of 10 patients with severe CAP with the aid of PCR amplification. Viral infection appears to be independently associated with lower mortality.


Assuntos
Influenza Humana/diagnóstico , Reação em Cadeia da Polimerase Multiplex , Infecções por Picornaviridae/diagnóstico , Pneumonia Bacteriana/diagnóstico , Pneumonia Pneumocócica/diagnóstico , Pneumonia Viral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/mortalidade , Infecções Comunitárias Adquiridas/virologia , Feminino , Mortalidade Hospitalar , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/mortalidade , Influenza Humana/virologia , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infecções por Picornaviridae/mortalidade , Infecções por Picornaviridae/virologia , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/mortalidade , Pneumonia Pneumocócica/microbiologia , Pneumonia Pneumocócica/mortalidade , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Estudos Prospectivos , Rhinovirus/genética , Streptococcus pneumoniae/genética
17.
Transfusion ; 55(7): 1655-61, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25728040

RESUMO

BACKGROUND: Blood-borne infections remain a risk of blood transfusions. While routine screening of donated blood products has greatly reduced the risk of human immunodeficiency virus, hepatitis B, and hepatitis C transmission, arboviruses such as dengue, chikungunya, and the West Nile virus remain significant risks especially during outbreaks. CASE REPORT: We report a rare case of dengue documented to be acquired through a blood transfusion, which resulted in severe thrombocytopenia prolonging admission in hospital in a neurosurgical patient. RESULTS: The donor of one of the units of red blood cells presented with dengue fever 2 days after donating. Sanger sequencing confirmed DENV-2 (dengue virus, Serotype 2) in both the donor and the patient samples and showed 100% nucleotide sequence identity between the two viruses, confirming transfusion-transmitted dengue infection. CONCLUSION: This case highlights the importance of arboviral screening of donor blood, especially for populations in endemic areas during outbreaks.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Vírus da Dengue , Dengue , Transfusão de Eritrócitos , Eritrócitos/virologia , Procedimentos Neurocirúrgicos/efeitos adversos , Adulto , Dengue/sangue , Dengue/transmissão , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Feminino , Humanos
18.
Mol Cell Probes ; 29(1): 74-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25462104

RESUMO

The aim of our study was to establish an unlabeled probe genotyping approach for rapid detection of the MYD88 L265P mutation in the differential diagnosis of WaldenstrÓ§m macroglobulinemia patients. Analytical and clinical validation of the assay was performed using serially diluted amplicon-cloned standards, 14 clinical bone marrow aspirate samples, and 30 peripheral blood samples from healthy donors, respectively. The analytical validation results showed that the assay is able to reproducibly identify as low as 10% of the L265P mutant. Clinical validation results showed improved detection sensitivity for the L265P mutation compared to Sanger sequencing. With the simplicity, cost-effectiveness, specificity and rapidity, we foresee that the unlabeled probe HRM assay is a good alternative to substitute current established methods for routine diagnostic testing of the MYD88 L265P mutation.


Assuntos
Antígenos de Diferenciação/genética , Técnicas de Diagnóstico Molecular/métodos , Sondas de Oligonucleotídeos/genética , Macroglobulinemia de Waldenstrom/diagnóstico , Genótipo , Humanos , Leucina/genética , Técnicas de Diagnóstico Molecular/economia , Mutação , Prolina/genética , Reprodutibilidade dos Testes , Análise de Sequência de DNA , Macroglobulinemia de Waldenstrom/líquido cefalorraquidiano , Macroglobulinemia de Waldenstrom/genética
19.
Clin Chem Lab Med ; 53(8): 1189-95, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25581758

RESUMO

BACKGROUND: Prenatal diagnosis of sex-linked disorders requires invasive procedures, carrying a risk of miscarriage of up to 1%. Cell-free fetal DNA (cffDNA) present in cell-free DNA (cfDNA) from maternal plasma offers a non-invasive source of fetal genetic material for analysis. Detection of Y-chromosome sequences in cfDNA indicates presence of a male fetus; in the absence of a Y-chromosome signal a female fetus is inferred. We aimed to validate the clinical utility of insertion-deletion polymorphisms (INDELs) to confirm presence of a female fetus using cffDNA. METHODS: Quantitative real-time PCR (qPCR) for the Y-chromosome-specific sequence, SRY, was performed on cfDNA from 82 samples at 6-39 gestational weeks. In samples without detectable SRY, qPCRs for eight INDELs were performed on maternal genomic DNA and cfDNA. Detection of paternally inherited fetal alleles in cfDNA negative for SRY confirmed a female fetus. RESULTS: Fetal sex was correctly determined in 77/82 (93.9%) cfDNA samples. SRY was detected in all 39 samples from male-bearing pregnancies, and none of the 43 female-bearing pregnancies (sensitivity and specificity of SRY qPCR is therefore 100%; 95% CI 91%-100%). Paternally inherited fetal alleles were detected in 38/43 samples with no SRY signal, confirming the presence of a female fetus (INDEL assay sensitivity is therefore 88.4%; 95% CI 74.1%-95.6%). Since paternally inherited fetal INDELs were not used in women bearing male fetuses, the specificity of INDELs cannot be calculated. Five cfDNA samples were negative for both SRY and INDELS. CONCLUSIONS: We have validated a non-invasive prenatal test to confirm fetal sex as early as 6 gestational weeks using cffDNA from maternal plasma.


Assuntos
DNA/sangue , DNA/genética , Feto , Mães , Polimorfismo Genético/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise para Determinação do Sexo/métodos , Proteína da Região Y Determinante do Sexo/genética , Alelos , Cromossomos Humanos Y/genética , Feminino , Deleção de Genes , Humanos , Gravidez , Diagnóstico Pré-Natal , Sensibilidade e Especificidade , Sexo
20.
J Clin Microbiol ; 52(5): 1749-50, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24599981

RESUMO

An immunocompromised child with influenza A/H3N2 virus infection, treated with oseltamivir from day 1, had nasal swabs taken on days 1, 4, 7, and 10 of the illness. Pyrosequencing showed increasing proportions of viruses with R292K (neuraminidase gene) and G186D (hemagglutinin gene) mutations, resulting in a viral load rebound by day 10.


Assuntos
Genes Virais/genética , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Mutação/genética , Oseltamivir/uso terapêutico , Criança , Feminino , Humanos , Hospedeiro Imunocomprometido/efeitos dos fármacos , Carga Viral/genética
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