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1.
ACS Appl Mater Interfaces ; 13(11): 13106-13113, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33720695

RESUMO

Oil spill rapidly destroys aquatic system and threatens humans, requiring fast and efficient remedy for removal of oil. The conventional remedy employs water-floating oil adsorbents whose volume should be large enough to accommodate all oil ingredients. Here, we suggest a new concept for efficient oil-spill remediation, which combines solar-driven evaporation of light oil components and simultaneous adsorption of heavy oil components, namely, solar-driven evaporation of oil combined with adsorption (SEOA). To design photothermal oil absorbents for the efficient SEOA, we designed carbonaceous fabrics with high photothermal heating performance and oil-adsorption capacity by carbonizing nonwoven cotton fabrics. For three model organic solvents of octane, decane, and dodecane floating on water, the fabrics, respectively, accelerated the evaporation in factors of 2.0, 4.4, and 2.3 through photothermal heating under simulated sunlight condition. For the 1.18 mm thick crude oil floating on water, 70 and 77 wt % of crude oil were evaporated within 2 and 16 h, respectively, with the photothermal fabrics, whereas only 22 and 34 wt % was evaporated in the absence of the fabrics, indicating the dramatic enhancement of oil removal by solar-driven evaporation. The remaining heavy oil components were accommodated in the pores of the fabrics, removal of which showed an additional 18 wt % reduction; that is, a total 95 wt % of the crude oil was removed. The oil-treatment capacity is as high as 110 g g-1, which has never been achieved with conventional oil adsorbents to the best of our knowledge. We believe that our combinatorial SEOA approach potentially contributes to minimizing the environmental disaster through a fast and efficient oil-spill remediation.

2.
PLoS One ; 15(2): e0228670, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32045455

RESUMO

BACKGROUND: Complex mosaic structures of HIV-1 were found in the Democratic Republic of Congo (DRC). Currently, there is limited information on the circulating HIV-1 strains, the distribution of these strains and antiretroviral (ART) resistant viruses in different regions of the country, and the HIV-1 strains harbored by the high-risk groups like female sex workers (FSW) reported to be the source of recombinant and ART resistant viruses. METHODS: Dried Blood Spots (DBS), collected from 325 infected FSWs in ten cities from 2012 DRC HIV/STI Integrated Biological and Behavioral Surveillance Survey, were tested for HIV-1 genotypes and antiretroviral resistance mutations. Regional segregation of HIV-1 clades was detected using phylogenetics. The significance for differences in HIV-1 subtype and drug resistance mutations were evaluated using Chi-square tests. RESULTS: There were 145 (env) and 93 (pol) sequences analyzed. Based on env sequences, the predominant subtype was A1 (44%), and recombinants as defined pol sequences comprised 35% of the total sample. Paired sequences of pol and env from DRC FSW revealed mosaic recombinant in 54% of the sequences. Distinct geographic distributions of different HIV-1 subtypes and recombinants were observed. Subtype A1 was prevalent (40%) in Goma located in the East and significantly higher than in Mbuji-Mayi (p<0.05) in the South-central region, or in Lubumbashi in the South. Antiretroviral resistance was detected in 21.5% of 93 pol sequences analyzed, with the M184I/V and K103N mutations that confer high-level resistance to NRTI and NNRTI, respectively, being the most frequent mutations. However, the K103N mutant viruses were found only in the East. CONCLUSION: HIV-1 variants found in DRC FSW reflect those reported to circulate in the general population from the corresponding geographical locations. HIV-1 mosaic genetics were readily detected in FSW. Importantly, ART resistance mutations to NNRTI and NRTI were common in the DRC sex workers.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/virologia , HIV-1/genética , Profissionais do Sexo/estatística & dados numéricos , Adolescente , Adulto , Cidades/epidemiologia , República Democrática do Congo , Feminino , Infecções por HIV/epidemiologia , HIV-1/classificação , Humanos , Pessoa de Meia-Idade , Mutação
3.
J Infect Dis ; 219(8): 1318-1328, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30452681

RESUMO

BACKGROUND: Kaposi sarcoma (KS)-associated herpesvirus (KSHV) is etiologically linked to all KS forms, but mechanisms underlying KS development are unclear. The incidence of KS in human immunodeficiency virus type 1-infected (HIV-1+) individuals implicates immune dysregulation; however, the lack of characterization of KSHV immune responses in endemic KS makes the role of HIV-1 unclear. The study objective was to investigate the HIV-1 and KSHV roles in viral nucleic acid detection, antibody responses, and cytokine responses in polymerase chain reaction-confirmed epidemic KS and endemic KS patients and non-cancer controls from sub-Saharan Africa. METHODS: KSHV viral DNA (vDNA), total anti-KSHV antibody, KSHV neutralizing antibody (nAb), and cytokines were quantified. RESULTS: KSHV vDNA was detectable in tumors but variably in plasma and peripheral blood mononuclear cells. Consistent with elevated antibody-associated cytokines (interleukin [IL] 6, IL-5, and IL-10), nAb titers were higher in epidemic KS and endemic KS patients than in controls (P < .05). Despite HIV-1 coinfection in epidemic KS, nAb titers were similar between epidemic KS and endemic KS patients (P = 0.3). CONCLUSIONS: Similarities in antibody and cytokine responses between epidemic and endemic KS patients suggest that KSHV drives KS pathogenesis, whereas HIV-1 exacerbates it.


Assuntos
Infecções por HIV/complicações , HIV-1 , Herpesvirus Humano 8/imunologia , Sarcoma de Kaposi/etiologia , Adulto , Idoso , Estudos de Casos e Controles , Coinfecção/imunologia , Coinfecção/virologia , DNA Viral/genética , Feminino , Citometria de Fluxo , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , Herpesvirus Humano 8/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Sarcoma de Kaposi/virologia , Tanzânia , Carga Viral , Adulto Jovem , Zâmbia
4.
PLoS One ; 13(7): e0201325, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30040863

RESUMO

Subtype C HIV-1 is responsible for the largest proportion of people living with HIV-1 infection. However, there is limited information about the roles of the brain and its cell types as a potential sanctuary for this subtype and how the sanctuary may be affected by the administration of anti-retroviral therapy (ART). To address this issue, we collected postmortem brain tissues from ART treated HIV-1 infected Zambian individuals who experienced complete viral suppression and those who did not. Tissues from various brain compartments were collected from each individual as frozen and formalin-fixed paraffin embedded brain specimens, for detection and quantification of HIV-1 genomes and identification of the infected cell type. Genomic DNA and RNA were extracted from frozen brain tissues. The extracted DNA and RNA were then subjected to droplet digital PCR for HIV-1 quantification. RNA/DNAscope in situ hybridization (ISH) for HIV-1 was performed on formalin-fixed paraffin embedded brain tissues in conjugation with immunohistochemistry to identify the infected cell types. Droplet digital PCR revealed that HIV-1 gag DNA and RNA were detectable in half of the cases studied regardless of ART success or failure. The presence of HIV-1 lacked specific tissue compartmentalization since detection was random among various brain tissues. When combined with immunohistochemistry, RNA/DNAscope ISH demonstrated co-localization of HIV-1 DNA with CD68 expressing cells indicative of microglia or peripheral macrophage. Our study showed that brain is a potential sanctuary for subtype C HIV-1, as HIV-1 can be detected in the brain of infected individuals irrespective of ART treatment outcome and no compartmentalization of HIV-1 to specific brain compartments was evident.


Assuntos
Antirretrovirais/uso terapêutico , Encéfalo/virologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , HIV-1/isolamento & purificação , Adolescente , Adulto , Encéfalo/patologia , Feminino , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/genética , Humanos , Masculino , RNA Viral/análise , RNA Viral/genética , Resultado do Tratamento , Replicação Viral/efeitos dos fármacos , Produtos do Gene gag do Vírus da Imunodeficiência Humana/análise , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
5.
PLoS Pathog ; 14(1): e1006844, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29352292

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiologic agent of Kaposi's sarcoma (KS). It is endemic in a number of sub-Saharan African countries with infection rate of >50%. The high prevalence of HIV-1 coupled with late presentation of advanced cancer staging make KS the leading cancer in the region with poor prognosis and high mortality. Disease markers and cellular functions associated with KS tumorigenesis remain ill-defined. Several studies have attempted to investigate changes of the gene profile with in vitro infection of monoculture models, which are not likely to reflect the cellular complexity of the in vivo lesion environment. Our approach is to characterize and compare the gene expression profile in KS lesions versus non-cancer tissues from the same individual. Such comparisons could identify pathways critical for KS formation and maintenance. This is the first study that utilized high throughput RNA-seq to characterize the viral and cellular transcriptome in tumor and non-cancer biopsies of African epidemic KS patients. These patients were treated anti-retroviral therapy with undetectable HIV-1 plasma viral load. We found remarkable variability in the viral transcriptome among these patients, with viral latency and immune modulation genes most abundantly expressed. The presence of KSHV also significantly affected the cellular transcriptome profile. Specifically, genes involved in lipid and glucose metabolism disorder pathways were substantially affected. Moreover, infiltration of immune cells into the tumor did not prevent KS formation, suggesting some functional deficits of these cells. Lastly, we found only minimal overlaps between our in vivo cellular transcriptome dataset with those from in vitro studies, reflecting the limitation of in vitro models in representing tumor lesions. These findings could lead to the identification of diagnostic and therapeutic markers for KS, and will provide bases for further mechanistic studies on the functions of both viral and cellular genes that are involved.


Assuntos
Metabolismo Energético/genética , Glucose/metabolismo , Metabolismo dos Lipídeos/genética , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/metabolismo , Infecções Oportunistas Relacionadas com a AIDS/genética , Infecções Oportunistas Relacionadas com a AIDS/metabolismo , Adulto , DNA Viral/análise , HIV-1 , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Sarcoma de Kaposi/virologia , Análise de Sequência de RNA , Tanzânia , Carga Viral/genética , Zâmbia
6.
J Infect Dis ; 215(12): 1898-1907, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27932611

RESUMO

Background: Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi sarcoma (KS), one of the leading cancers in human immunodeficiency virus (HIV)-infected patients in Zambia. KSHV was detected in the human central nervous system (CNS) by polymerase chain reaction (PCR) analysis, but tissue location and cell tropism for KSHV infection has not been established. Given the neurotropism exhibited by other herpesviruses and the frequent coinfection of HIV-positive individuals by KSHV, we sought to determine whether the central nervous system (CNS) can be infected by KSHV in HIV-positive Zambian individuals. Methods: Postmortem brain tissue specimens were collected from individuals coinfected with KSHV and HIV. PCR and Southern blots were performed on DNA extracted from the brain tissue specimens to verify KSHV infection. Immunohistochemical analysis and immunofluorescent microscopy were used to localize and identify KSHV-infected cells. Tropism was further established by in vitro infection of primary human neurons with rKSHV.219. Results: KSHV DNA was detected in the CNS from 4 of 11 HIV-positive individuals. Immunohistochemical analysis and immunofluorescent microscopy demonstrated that KSHV infected neurons and oligodendrocytes in parenchymal brain tissues. KSHV infection of neurons was confirmed by in vitro infection of primary human neurons with rKSHV.219. Conclusion: Our study showed that KSHV infects human CNS-resident cells, primarily neurons, in HIV-positive Zambian individuals.


Assuntos
Infecções do Sistema Nervoso Central/complicações , Infecções por HIV/complicações , Herpesvirus Humano 8 , Neurônios/virologia , Sarcoma de Kaposi/complicações , Adulto , DNA Viral/análise , Feminino , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Sarcoma de Kaposi/patologia , Adulto Jovem , Zâmbia
7.
Clin Hemorheol Microcirc ; 40(4): 315-24, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19126995

RESUMO

Irradiation has been shown to induce biochemical changes in stored red blood cells (RBCs) and to generate reactive oxygen species (ROS). This study evaluated the hemorheological properties, the degree of lipid peroxidation and the oxidative susceptibility of irradiated RBCs. Furthermore, we investigated the radioprotective role of N-t-butyl hydroxylamine (NtBHA) against gamma-ray exposure of RBCs. RBC concentrates were irradiated with a minimum dose of 25 Gy, and were exposed to FeSO4 to examine the oxidative susceptibility. RBC deformability was evaluated by the use of a microfluidic ektacytometer, in relation to the hematological and biochemical properties. The deformability of the irradiated RBCs was significantly lower than that of control. Exposure to gamma rays significantly increased the mean corpuscular volume (MCV) and lipid peroxidation. Changes in RBC deformability were more prominent in irradiated RBCs than in non-irradiated RBCs also under conditions of oxidative stress. The deformability of NtBHA treated RBCs prior to irradiation was not altered as compared with irradiated RBCs not treated with NtBHA. In conclusion, irradiation reduces RBC deformability during storage and the irradiated RBCs seem susceptible to oxidative stress. NtBHA may not have a protective role against the effects of gamma-ray exposure in RBCs but further evaluation of NtBHA or another radioprotective compound is required.


Assuntos
Deformação Eritrocítica/efeitos da radiação , Eritrócitos/efeitos da radiação , Raios gama/efeitos adversos , Estresse Oxidativo/efeitos da radiação , Preservação de Sangue/efeitos adversos , Humanos , Hidroxilaminas/uso terapêutico , Peroxidação de Lipídeos/efeitos da radiação , Protetores contra Radiação/uso terapêutico
8.
Phytother Res ; 17(8): 882-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-13680817

RESUMO

We determined whether Asiasari Radix (AR) extracts have protective actions in brain cells. Methanol extracts of Asiasari Radix (fraction 1) have significant inhibitory effects on the AMPA-induced rat cortical depolarization in the grease gap assay. In differentiated PC12 cells, it almost completely protected against AMPA-induced cell death. In addition, it had some protective actions in C6 glial cells death induced by AMPA. The methanol extracts (fraction 1) of AR were subsequently fractionated into chloroform-(fraction 2), chloroform/methanol-(3:1) (fraction 3), methanol-soluble (fraction 4) and methanol-insoluble, water-soluble fractions (fraction 5). Among these, fraction 4 had the strongest inhibitory effects against AMPA-induced cell death in the PC 12 cells and also dramatically inhibited AMPA-induced depolarization of rat brain cortex in the grease gap assay. Interestingly, fraction 4 blocked the Zn-induced oxidative damages in C6 glial cells.


Assuntos
Asarum , Encefalopatias/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Encefalopatias/induzido quimicamente , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Masculino , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Células PC12/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
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