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1.
J Integr Neurosci ; 23(1): 12, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38287842

RESUMO

BACKGROUND: The acute changes that occur in the small-world topology of the brain in concussion patients remain unclear. Here, we investigated acute changes in the small-world organization of brain networks in concussion patients and their influence on persistent post-concussion symptoms. METHODS: Eighteen concussion patients and eighteen age-matched controls were enrolled in this study. All participants underwent computed tomography, magnetic resonance imaging (MRI), susceptibility weighted imaging, and blood oxygen level-dependent functional MRI. A complex network analysis method based on graph theory was used to calculate the parameters of small-world networks under different degrees of network sparsity. All subjects were evaluated using the Glasgow Coma Scale and Rivermead Postconcussion Symptom Questionnaire. RESULTS: Compared with the controls, the normalized cluster coefficient (γ) of whole brain networks in patients and the "small-world" index (σ) was slightly enhanced, whereas the standardized minimum path (λ) was slightly shorter. Whole brain effect (Eglobal) and local effect (Elocal) changes were not pronounced. Under the condition of minimum network sparsity (Dmin = 0.13), the numbers of nodes in the "right intraorbital superior frontal gyrus" (Anatomical Automatic Labeling, AAL26), right globus pallidus (AAL76), and bilateral temporal transverse gyrus (AAL79,80) in brain concussion patients were significantly lower. The numbers of nodes in the left subcapital lobe (AAL61) and left occipital gyrus (AAL51) were significantly higher, and the normalized cluster coefficients of the right intraorbital supraphalus (AAL26) and left posterior cingulate gyrus (AAL35) were significantly increased. The normalized clustering coefficients of the right triangular subfrontal gyrus (AAL55) (based on the normalized clustering coefficients of nodes in AAL14) and left sub-parietal lobes (AAL61) were significantly reduced. The mean local effects of nodes in the right intraorbital upper frontal gyrus (AAL26), left posterior cingulate gyrus (AAL35), and bilateral auxiliary motor cortex (AAL19, 20) were enhanced, whereas the mean local effects of the bilateral triangular inferior frontal gyrus (AAL13,14) and left insular cap (AAL11) were reduced (p < 0.05). CONCLUSIONS: The overall trend of network topology abnormalities in patients was random, and generalized and local functional abnormalities were seen. Changes in the function and affective circuitry of the resting default network were particularly pronounced in these patients, which we speculate may be one of the main drivers of the cognitive dysfunction and mood changes seen in concussion patients.


Assuntos
Concussão Encefálica , Humanos , Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/patologia , Encéfalo , Mapeamento Encefálico/métodos , Lobo Parietal , Lobo Frontal , Imageamento por Ressonância Magnética/métodos
2.
Mol Carcinog ; 62(4): 532-545, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36752341

RESUMO

MiR-1283 has been identified as a tumor suppressor in some malignancies. Whereas, the role of miR-1283 in HER2-positive (HER2+) breast cancer, particularly its role in regulating cell proliferation, one of the most significant features of tumor progression, is unclear. The related microRNA screened by the breast cancer sample GSE131599 dataset were detected in HER2+ breast cancer tissues and cell lines. Then, the obtained miR-1283 was overexpressed in SKBR3 and BT-474 cells followed by relevant functional assays concerning cell proliferation and apoptosis. The xenograft mouse model was induced and the effect of miR-1283 on tumor growth and cell proliferation was examined. The target of miR-1283 and the transcription factor regulating miR-1283 were predicted and identified. Finally, the influence of transcription factor KLF14 on cell proliferation and apoptosis was investigated. An integrated analysis confirmed that miR-1283 expression was significantly decreased in HER2+ breast cancer tissues. Also, by q-RT-PCR detection, miR-1283 expression was markedly reduced in HER2+ breast cancer tissues and cell lines. The miR-1283 overexpression prevented the proliferation and enhanced apoptosis of HER2+ breast cancer cells, as well as inhibited tumor growth. Mechanistically, miR-1283 inhibited TFAP2C expression by targeting the 3'-untranslated regions of TFAP2C messenger RNA, and the KLF14 enhanced miR-1283 level via binding to its promoter. The result subsequently confirmed the KLF14/miR-1283 signaling suppressed cell proliferation in HER2+ breast cancer. Our results suggested that the KLF14/miR-1283/TFAP2C axis inhibited HER2+ breast cancer progression, which might provide novel insight into mechanical exploration for this disease.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Animais , Camundongos , Feminino , Linhagem Celular Tumoral , Neoplasias da Mama/metabolismo , MicroRNAs/metabolismo , Proliferação de Células/genética , Fatores de Transcrição/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Fator de Transcrição AP-2/genética
3.
Anal Biochem ; 682: 115339, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37805041

RESUMO

In the peel of citrus (Rutaceae) fruit, hesperitin (Hesp), a flavanone glycoside chemical, is found naturally. Hesp has been found to have a wide range of pharmacological actions, including anti-inflammatory, antioxidant, antiviral, and anticancer properties, according to earlier research. However, nothing is known regarding its function in alcoholic liver steatosis and inflammation. In this study, we employed a network pharmacology approach to identify the TLR4 signaling pathway as a primary target of Hesp for the treatment of alcoholic steatohepatitis (ASH). Molecular docking results showed that Hesp bound to the representative target TLR4 and exhibited good affinity. In addition, Hesp inhibits the TLR4 target and consequently the NF-κB signaling pathway, which in turn slows the evolution of alcoholic steatohepatitis, according to further in vitro and in vivo tests. The results of this study preliminarily indicate that Hesp is an ideal drug candidate for the treatment of ASH.


Assuntos
Fígado Gorduroso Alcoólico , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Fígado Gorduroso Alcoólico/tratamento farmacológico , Receptor 4 Toll-Like/metabolismo , Simulação de Acoplamento Molecular , Transdução de Sinais
4.
Appl Opt ; 62(4): 880-885, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36821140

RESUMO

This paper presents a nitrogen dioxide detection device based on gas absorption spectroscopy by connecting two integrating spheres as a gas cell, observing the feasibility of the tandem integrating spheres as a gas cell, and taking a single integrating sphere as a gas cell for comparison experiments. Theoretical knowledge of the effective path length of tandem integrating spheres was established, and the theoretical derivation was further verified by experiments investigating the relationship between absorbance and gas concentration. This work makes it possible to develop a gas sensor that can reduce the volume of the gas cell and keep the effective optical path length unreduced.

5.
Opt Express ; 30(22): 39679-39690, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298914

RESUMO

A novel integrated surface plasmon resonance (SPR) sensor that combines an optical waveguide platform and an ultra-thin spectrometer is proposed. The core of the proposed method is a special-shaped optical waveguide structure that employs a wedge-shaped incident surface, which changes the position of the total reflection of the incident light on the sagittal plane without affecting the direction of propagation on the tangential plane. The parameters of the sensing module with the integrated SPR sensor and spectrometer module were designed and optimized to achieve higher performance in a compact optical waveguide platform. An experimental system was built based on the theoretical model, and the spectral sensitivity of the system was analyzed before sample detection, and the results showed that the spectral resolution in the working range could reach 9.9 nm. The refractive index sensitivity of this novel SPR sensor was 3186 nm/RIU with good stability by detecting different concentrations of sodium chloride samples. This new structure does not require an external spectrometer, thereby enabling an increase in the compactness of the SPR sensing system. The proposed method can provide a novel idea for the miniaturization of SPR sensors.

6.
Emerg Infect Dis ; 27(6): 1742-1745, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34013865

RESUMO

Hepatitis A virus (HAV) genotype IA was most common among strains tested in US outbreak investigations and surveillance during 1996-2015. However, HAV genotype IB gained prominence during 2016-2019 person-to-person multistate outbreaks. Detection of previously uncommon strains highlights the changing molecular epidemiology of HAV infection in the United States.


Assuntos
Vírus da Hepatite A , Hepatite A , Surtos de Doenças , Genótipo , Hepatite A/epidemiologia , Vírus da Hepatite A/genética , Humanos , Epidemiologia Molecular , Filogenia , RNA Viral , Estados Unidos
7.
J Transl Med ; 19(1): 455, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732216

RESUMO

BACKGROUND: Circular RNAs (circRNAs) are pivotal regulators of various human cancers and circ-ERBB2 is abnormally expressed in breast cancer cells. However, the role and mechanism of circ-ERBB2 in HER2-positive breast cancer are still unknown. METHODS: The circ-ERBB2 expressions in the tumor tissues of HER2-positive breast cancer patients were tested using quantitative real-time PCR. The circ-ERBB2 function was investigated by cell counting kit 8 assay, Transwell, flow cytometry and Western blot. Mechanistically, fluorescence in situ hybridization, RNA immunoprecipitation, RNA pull-down and dual-luciferase reporter gene assays were conducted to confirm the interaction between circ-ERBB2 and miR-136-5p or miR-198 in HER2-positive breast cancer cells. RESULTS: Circ-ERBB2 was elevated in the tumor tissues of HER2-positive breast cancer patients. Functionally, the interference with circ-ERBB2 repressed HER2-positive breast cancer cell proliferation, migration, invasion and accelerated cell apoptosis. Furthermore, the mechanistic analysis corroborated that circ-ERBB2 acted as a competing endogenous RNA for miR-136-5p or miR-198 to relieve the repressive influence of miR-136-5p or miR-198 on its target transcription factor activator protein 2C (TFAP2C). Meanwhile, in vivo assays further corroborated the oncogenic function of circ-ERBB2 in HER2-positive breast cancer. CONCLUSIONS: Circ-ERBB2 accelerated HER2-positive breast cancer progression through the circ-ERBB2/miR-136-5p/TFAP2C axis or the circ-ERBB2/miR-198/TFAP2C axis.


Assuntos
Neoplasias da Mama , MicroRNAs , Neoplasias da Mama/genética , Proliferação de Células , Feminino , Humanos , Hibridização in Situ Fluorescente , MicroRNAs/genética , RNA Circular , Receptor ErbB-2/genética
8.
Anal Biochem ; 619: 114130, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33600781

RESUMO

Lateral flow assays (LFAs) are extensively used in qualitative detection because of their convenience, low cost, fast results, and ease of operation. However, the sample volume used in a lateral flow assay is usually determined experimentally. We test and find that the flow velocity is influenced by sample volume, using fluorescent microspheres as label particles, when analyte concentration is fixed in a sandwich LFA. A model is developed based on mass-action kinetics and advection-diffusion-reaction equation, combing the conjugate pad and nitrocellulose membrane. The model shows predictions from 10 to 120 µL, and predicts accurately the experimental results from 50 to 120 µL where the fluid can flow to the test line. Over all, the model can provide predictions over a wide range of sample volumes for sensitivity analysis. On the basis of the model, the sensitivity of the LFA can be improved according to the sample volume added in the experiment.


Assuntos
Simulação por Computador , Microesferas , Modelos Teóricos
9.
Appl Opt ; 60(5): 1273-1282, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33690570

RESUMO

Spectral bandwidth correction is an effective way to obtain the original spectrum. However, the correct selection of optimal parameters used to recover the distortion spectrum in bandwidth correction algorithms has always been an important problem. To overcome the shortcomings of traditional parameter selection methods and obtain the optimal parameter, we propose a new optimal parameter selection method based on deep learning (DL). First, the database and neural network were constructed, and then the optimal parameters of corresponding algorithms were obtained through the training of the neural network. In order to verify the superiority of the optimal parameter selection method based on DL, the Levenberg-Marquardt (L-M) and Richardson-Lucy (R-L) algorithms with corresponding optimal parameters were compared with the traditional L-M and R-L algorithms to recover the distortion white light-emitting diode, Raman spectrum, and compact fluorescent lamp spectrum. The type A uncertainty and root mean square error values of the different cases were calculated. The results proved that, compared with the traditional methods for obtaining the optimal parameters, the neural network was capable of obtaining parameters that can make the bandwidth correction algorithm more efficient at recovering the distorted spectrum.

10.
Sensors (Basel) ; 21(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33418864

RESUMO

A unique method to design a high-throughput and high-resolution ultrathin Czerny-Turner (UTCT) spectrometer is proposed. This paper reveals an infrequent design process of spectrometers based on Coddington's equations, which will lead us to develop a high-performance spectrometer from scratch. The spectrometer is composed of cylindrical elements except a planar grating. In the simulation design, spot radius is sub-pixel size, which means that almost all of the energy is collected by the detector. The spectral resolution is 0.4 nm at central wavelength and 0.75 nm at edge wavelength when the width of slit is chosen to be 25 µm and the groove density is 900 lines/mm.

11.
Sensors (Basel) ; 21(2)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477610

RESUMO

Refractive index resolution is an important indicator for a wavelength interrogation surface plasmon resonance sensor, which can be affected by signal-to-noise ratio. This paper investigates the impact of spectral signal-to-noise ratio on a surface plasmon resonance sensor. The effects of different spectral powers and noises are compared and verified through simulation and experiments. The results indicate that the optimal resonance wavelength is changed and the refractive index resolution can even be nearly twice as good when the spectral signal-to-noise ratio is increased. The optimal resonance wavelength can be found by changing the spectral power distribution or noise.

12.
Opt Express ; 28(8): 11227-11236, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403637

RESUMO

Simultaneous multipolarization and high-resolution oxygen A-band spectrometer (SPHABS) is proposed. The astigmatism correction theory is used to separate beams from different fields of view and make it possible to obtain multiple polarization information simultaneously. SPHABS' design and the basic principle of SPHABS and the astigmatism correction theory are elaborated in detail. The ray-tracing results of the model showed that the resolution reached 0.016 nm and information from four fields of view could be obtained simultaneously on the image surface.

13.
Bioinformatics ; 34(1): 163-170, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29304222

RESUMO

Motivation: Genomic analysis has become one of the major tools for disease outbreak investigations. However, existing computational frameworks for inference of transmission history from viral genomic data often do not consider intra-host diversity of pathogens and heavily rely on additional epidemiological data, such as sampling times and exposure intervals. This impedes genomic analysis of outbreaks of highly mutable viruses associated with chronic infections, such as human immunodeficiency virus and hepatitis C virus, whose transmissions are often carried out through minor intra-host variants, while the additional epidemiological information often is either unavailable or has a limited use. Results: The proposed framework QUasispecies Evolution, Network-based Transmission INference (QUENTIN) addresses the above challenges by evolutionary analysis of intra-host viral populations sampled by deep sequencing and Bayesian inference using general properties of social networks relevant to infection dissemination. This method allows inference of transmission direction even without the supporting case-specific epidemiological information, identify transmission clusters and reconstruct transmission history. QUENTIN was validated on experimental and simulated data, and applied to investigate HCV transmission within a community of hosts with high-risk behavior. It is available at https://github.com/skumsp/QUENTIN. Contact: pskums@gsu.edu or alexz@cs.gsu.edu or rahul@sfsu.edu or yek0@cdc.gov. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Quase-Espécies , Análise de Sequência de RNA/métodos , Software , Teorema de Bayes , Surtos de Doenças , Genômica/métodos , Hepacivirus/genética , Humanos , Análise de Sequência de DNA/métodos
14.
Transfusion ; 59(2): 601-611, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30499591

RESUMO

BACKGROUND: Characteristics of US blood donors with recent (RBI) or occult (OBI) hepatitis B virus (HBV) infection are not well defined. METHODS: Donors with RBI and OBI were identified by nucleic acid and serologic testing among 34.4 million donations during 2009-2015. Consenting donors were interviewed and their HBV S-gene sequenced. RESULTS: The overall rate of HBV-infected donors was 7.95 per 100,000; of these, 0.35 per 100,000 and 1.70 per 100,000 were RBI and OBI, respectively. RBI (n = 120) and OBI (n = 583) donors constituted 26% of all HBV-infected (n = 2735) donors. Detection of HBV DNA in 92% of OBI donors required individual donation nucleic acid testing. Donors with OBI compared to RBI were older (mean age, 48 vs 39 years; p < 0.0001) with lower median viral loads (9 vs. 529 IU/mL; p < 0.0001). A higher proportion of OBI than RBI donors were born or resided in an endemic country (39% vs. 5%; p = 0.0078). Seventy-seven percent of all RBI and OBI donors had multiple sex partners, an HBV-risk factor. Of 40 RBI and 10 OBI donors whose S gene was sequenced, 33 (83%) and 6 (60%), respectively, carried HBV subgenotype A2; 18 (55%) and 2 (33%), respectively, shared an identical sequence. Infection with 1 or more putative HBV-immune-escape mutants was identified in 5 (50%) of OBI but no RBI donors. CONCLUSION: RBI and OBI continue to be identified at low rates, confirming the importance of comprehensive HBV DNA screening of US blood donations. HBV-infected donors require referral for care and evaluation and contact tracing; their HBV strains may provide important information on emergent genotypes.


Assuntos
Doadores de Sangue , DNA Viral/sangue , Vírus da Hepatite B , Hepatite B Crônica , Adolescente , Adulto , Seleção do Doador , Feminino , Hepatite B Crônica/sangue , Hepatite B Crônica/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos/epidemiologia
15.
MMWR Morb Mortal Wkly Rep ; 68(18): 413-415, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31071072

RESUMO

Hepatitis A virus (HAV) is primarily transmitted fecal-orally after close contact with an infected person (1); it is the most common cause of viral hepatitis worldwide, typically causing acute and self-limited symptoms, although rarely liver failure and death can occur (1). Rates of hepatitis A had declined by approximately 95% during 1996-2011; however, during 2016-2018, CDC received approximately 15,000 reports of HAV infections from U.S. states and territories, indicating a recent increase in transmission (2,3). Since 2017, the vast majority of these reports were related to multiple outbreaks of infections among persons reporting drug use or homelessness (4). In addition, increases of HAV infections have also occurred among men who have sex with men (MSM) and, to a much lesser degree, in association with consumption of imported HAV-contaminated food (5,6). Overall, reports of hepatitis A cases increased 294% during 2016-2018 compared with 2013-2015. During 2016-2018, CDC tested 4,282 specimens, of which 3,877 (91%) had detectable HAV RNA; 565 (15%), 3,255 (84%), and 57 (<1%) of these specimens were genotype IA, IB, or IIIA, respectively. Adherence to the Advisory Committee on Immunization Practices (ACIP) recommendations to vaccinate populations at risk can help control the current increases and prevent future outbreaks of hepatitis A in the United States (7).


Assuntos
Surtos de Doenças , Hepatite A/epidemiologia , Vigilância da População , Notificação de Doenças/estatística & dados numéricos , Vírus da Hepatite A/genética , Vírus da Hepatite A/isolamento & purificação , Humanos , Incidência , Fatores de Risco , Estados Unidos/epidemiologia
16.
Twin Res Hum Genet ; 22(2): 79-87, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31012404

RESUMO

Type 2 diabetes (T2D) is a chronic disease that disproportionately affects Indigenous Australians. We have previously reported the localization of a novel T2D locus by linkage analysis to chromosome 2q24 in a large admixed Indigenous Australian pedigree (Busfield et al. (2002). American Journal of Human Genetics, 70, 349-357). Here we describe fine mapping of this region in this pedigree, with the identification of SNPs showing strong association with T2D: rs3845724 (diabetes p = 7 × 10-4), rs4668106 (diabetes p = 9 × 10-4) and rs529002 (plasma glucose p = 3 × 10-4). These associations were successfully replicated in an independent collection of Indigenous Australian T2D cases and controls. These SNPs all lie within the gene encoding ceramide synthase 6 (CERS6) and thus may regulate ceramide synthesis.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Proteínas de Membrana/genética , Esfingosina N-Aciltransferase/genética , Austrália/epidemiologia , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Polimorfismo de Nucleotídeo Único/genética
17.
Sensors (Basel) ; 19(5)2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30857251

RESUMO

Sensitivity is an important performance index for evaluating surface plasmon resonance (SPR) biosensors. Sensitivity enhancement has always been a hot topic. It is found that the different refractive indices of samples require different combinations of prism and metal film for better sensitivity. Furthermore, the sensitivity can be enhanced by coating two-dimensional (2D) materials with appropriate layers on the metal film. At this time, it is necessary to choose the best film configuration to enhance sensitivity. With the emergence of more and more 2D materials, selecting the best configuration manually is becoming more complicated. Compared with the traditional manual method of selecting materials and layers, this paper proposes an optimization method based on a genetic algorithm to quickly and effectively find the optimal film configuration that enhances sensitivity. By using this method, not only can the optimal number of layers of 2D materials be determined quickly, but also the optimal configuration can be conveniently found when many materials are available. The maximum sensitivity can reach 400°/RIU after optimization. The method provided application value for the relevant researchers seeking to enhance sensitivity.

18.
Clin Infect Dis ; 67(6): 845-853, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29767683

RESUMO

Background: In May 2012, the New Hampshire (NH) Division of Public Health Services (DPHS) was notified of 4 persons with newly diagnosed hepatitis C virus (HCV) infection at hospital X. Initial investigation suggested a common link to the hospital cardiac catheterization laboratory (CCL) because the infected persons included 3 CCL patients and a CCL technician. NH DPHS initiated an investigation to determine the source and control the outbreak. Methods: NH DPHS conducted site visits, case patient and employee interviews, medical record and medication use review, and employee and patient HCV testing using enzyme immunoassay for anti-HCV, reverse-transcription polymerase chain reaction for HCV RNA, nonstructural 5B (NS5B) and hypervariable region 1 (HVR1) sequencing, and quasispecies analysis. Results: HCV HVR1 analysis of the first 4 cases confirmed a common source of infection. HCV testing identified 32 of 1074 CCL patients infected with the outbreak strain, including 3 patients coinfected with >1 HCV strain. The epidemiologic investigation revealed evidence of drug diversion by the HCV-infected technician, evidenced by gaps in controlled medication control, higher fentanyl use during procedures for confirmed cases, and building card key access records documenting the presence of the technician during days when transmission occurred. The employee's status as a traveling technician led to a multistate investigation, which identified additional cases at prior employment sites. Conclusions: This is the largest laboratory-confirmed drug diversion-associated HCV outbreak published to date. Recommendations to reduce drug diversion risk and to conduct outbreak investigations are provided.


Assuntos
Infecção Hospitalar/epidemiologia , Surtos de Doenças , Hepatite C/epidemiologia , Hepatite C/etiologia , Laboratórios Hospitalares , Pessoal de Laboratório Médico , Desvio de Medicamentos sob Prescrição , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecção Hospitalar/virologia , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , New Hampshire/epidemiologia , Filogenia , RNA Viral/genética , Análise de Sequência de DNA
20.
J Gen Virol ; 98(5): 1048-1057, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28537543

RESUMO

Despite the significant public health problems associated with hepatitis B virus (HBV) in sub-Saharan Africa, many countries in this region do not have systematic HBV surveillance or genetic information on HBV circulating locally. Here, we report on the genetic characterization of 772 HBV strains from Tanzania. Phylogenetic analysis of the S-gene sequences showed prevalence of HBV genotype A (HBV/A, n=671, 86.9 %), followed by genotypes D (HBV/D, n=95, 12.3 %) and E (HBV/E, n=6, 0.8 %). All HBV/A sequences were further classified into subtype A1, while the HBV/D sequences were assigned to a new cluster. Among the Tanzanian sequences, 84 % of HBV/A1 and 94 % of HBV/D were unique. The Tanzanian and global HBV/A1 sequences were compared and were completely intermixed in the phylogenetic tree, with the Tanzanian sequences frequently generating long terminal branches, indicating a long history of HBV/A1 infections in the country. The time to the most recent common ancestor was estimated to be 188 years ago [95 % highest posterior density (HPD): 132 to 265 years] for HBV/A1 and 127 years ago (95 % HPD: 79 to 192 years) for HBV/D. The Bayesian skyline plot showed that the number of transmissions 'exploded' exponentially between 1960-1970 for HBV/A1 and 1970-1990 for HBV/D, with the effective population of HBV/A1 having expanded twice as much as that of HBV/D. The data suggest that Tanzania is at least a part of the geographic origin of the HBV/A1 subtype. A recent increase in the transmission rate and significant HBV genetic diversity should be taken into consideration when devising public health interventions to control HBV infections in Tanzania.

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