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1.
Traffic ; 23(5): 270-286, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35261124

RESUMO

Mitochondria and intermediate filament (IF) accumulations often occur during imbalanced axonal transport leading to various types of neurological diseases. It is still poorly understood whether a link between neuronal IFs and mitochondrial mobility exist. In Caenorhabditis elegans, among the 11 cytoplasmic IF family proteins, IFB-1 is of particular interest as it is expressed in a subset of sensory neurons. Depletion of IFB-1 leads to mild dye-filling and significant chemotaxis defects as well as reduced life span. Sensory neuron development is affected and mitochondrial transport is slowed down leading to reduced densities of these organelles. Mitochondria tend to cluster in neurons of IFB-1 mutants likely independent of the fission and fusion machinery. Oxygen consumption and mitochondrial membrane potential is measurably reduced in worms carrying mutations in the ifb-1 gene. Membrane potential also seems to play a role in transport such as carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone treatment led to increased directional switching of mitochondria. Mitochondria co-localize with IFB-1 in worm neurons and appear in a complex with IFB-1 in pull-down assays. In summary, we propose a model in which neuronal IFs may serve as critical (transient) anchor points for mitochondria during their long-range transport in neurons for steady and balanced transport.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Filamentos Intermediários/genética , Proteínas de Filamentos Intermediários/metabolismo , Filamentos Intermediários/metabolismo , Mitocôndrias/metabolismo , Células Receptoras Sensoriais/metabolismo
2.
Clin Chem Lab Med ; 62(5): 830-834, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37852014

RESUMO

The indirect immunofluorescence assay on HEp-2 cells (HEp-2 IFA) is still considered the reference method to detect anti-nuclear antibodies (ANA) because of its high sensitivity and represents a relevant tool for the diagnosis of autoimmune rheumatic diseases. During the last decade, the International Consensus on ANA Patterns (ICAP) initiative promoted harmonization and understanding of HEp-2 IFA staining pattern nomenclature, as well as promoting their use in patient care by providing interpretation for HEp-2 IFA test results. In conjunction with a nationwide survey on the evolution of autoantibody diagnostics in autoimmune rheumatic diseases, we focused on the adherence of the Italian laboratories to the ICAP nomenclature analyzing its lights and shadows. The recent ICAP-oriented report, largely used today among Italian laboratories, also represents a further step in harmonizing and improving communication with the clinicians, adding value to laboratory findings and helping with critical clinical decisions.


Assuntos
Doenças Autoimunes , Doenças Reumáticas , Humanos , Laboratórios Clínicos , Consenso , Anticorpos Antinucleares , Doenças Autoimunes/diagnóstico , Técnica Indireta de Fluorescência para Anticorpo/métodos , Itália
3.
Public Health Nutr ; 27(1): e149, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785047

RESUMO

OBJECTIVE: Research is available on improved coverage and practices from several large-scale maternal nutrition programmes, but not much is known on change in inequalities. This study analyses wealth and education inequality using Erreygers and Concentration indices for four indicators: adequate iron and folic acid (IFA) consumption, women's dietary diversity, and counselling on IFA and dietary diversity. DESIGN: A pre-test-post-test, control group design. SETTING: Maternal nutrition intervention programmes conducted in Bangladesh, Burkina Faso and Ethiopia during 2015-2022. PARTICIPANTS: Recently delivered women (RDW) and pregnant women (PW). RESULTS: Statistically significant reductions in education inequality were observed for adequate IFA consumption, counselling on IFA and dietary diversity in intervention areas of Bangladesh and for adequate IFA consumption in intervention areas of Burkina Faso.A significant decrease in wealth inequality was observed for adequate IFA consumption in the intervention areas of Bangladesh, whereas a significant increase was observed in the non-intervention areas for counselling on IFA in Ethiopia and for dietary diversity in Burkina Faso. CONCLUSION: The results can be attributed to the extensive delivery system at community level in Bangladesh and being predominantly facility-based in Burkina Faso and Ethiopia. COVID-19 disruptions (in Burkina Faso and Ethiopia) and indicator choice also had a role in the results.The main takeaways for nutrition programmes are as follows: (a) assessing inequality issues through formative studies during designing, (b) monitoring inequality indicators during implementation, (c) diligently addressing inequality through targeted interventions, setting aside resources and motivating frontline workers to reduce disparities and (d) making inequality analysis a routine part of impact evaluations.


Assuntos
Dieta , Ácido Fólico , Fenômenos Fisiológicos da Nutrição Materna , Fatores Socioeconômicos , Humanos , Feminino , Gravidez , Ácido Fólico/administração & dosagem , Etiópia , Bangladesh , Adulto , Dieta/estatística & dados numéricos , Burkina Faso , Países em Desenvolvimento , Adulto Jovem , Ferro/administração & dosagem , Gestantes , Ferro da Dieta/administração & dosagem , SARS-CoV-2
4.
Subcell Biochem ; 106: 197-210, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38159228

RESUMO

The cytopathic effect comprises the set of cellular alterations produced by a viral infection. It is of great relevance since it constitutes a direct marker of infection. Likewise, these alterations are often virus-specific which makes them a phenotypic marker for many viral species. All these characteristics have been used to complement the study of the dynamics of virus-cell interactions through the kinetic study of the progression of damage produced by the infection. Various approaches have been used to monitor the cytopathic effect, ranging from light microscopy, immunofluorescence assays, and direct labeling with fluorescent dyes, to plaque assay for the characterization of the infection over time. Here we address the relevance of the study of cytopathic effect and describe different experimental alternatives for its application.


Assuntos
Vírus , Efeito Citopatogênico Viral
5.
Emerg Infect Dis ; 29(2): 456-459, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36692499

RESUMO

We assessed serum samples collected in Cauca Department, Colombia, from 486 persons for Orientia seroreactivity. Overall, 13.8% showed reactive IgG by indirect immunofluorescence antibody assay and ELISA. Of those samples, 30% (20/67) were confirmed to be positive by Western blot, showing >1 reactive band to Orientia 56-kD or 47-kD antigens.


Assuntos
Orientia tsutsugamushi , Infecções por Rickettsia , Tifo por Ácaros , Humanos , Tifo por Ácaros/epidemiologia , Colômbia/epidemiologia , População Rural , Sensibilidade e Especificidade , Imunoglobulina M , Anticorpos Antibacterianos , Ensaio de Imunoadsorção Enzimática , Orientia
6.
BMC Public Health ; 23(1): 1923, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37794346

RESUMO

BACKGROUND: Compliance with the iron folic acid supplementation is low and not at the required level to prevent anaemia during pregnancy in many countries, including Ethiopia, even though an iron-folic acid supplementation program is being implemented. The aims of this study were to determine the effect of community-based nutritional education on knowledge, attitude, and compliance to IFA supplementation in Ilu Aba Bor zone of southwest Ethiopia. METHOD: A pretest-posttest quasi-experimental study design consisting of intervention and control group was conducted among pregnant women. The total sample size of 472, therefore, 236 pregnant women for each interventional and control group from 16 kebeles were randomly selected in two districts. A multi-stage sampling technique was used to select the study participants. Then, individual study units were selected using a simple random sampling technique and followed until the end of the study period. Effect of community-based nutritional education on knowledge, attitude, and compliance to IFA supplementation among pregnant women in rural areas were measured. RESULTS: A total of 472 pregnant women participated in the study during the baseline and 437 (92.6%) were in the study until the end. The majority (49.2%) of respondents were 21-25 years of age, with a mean age of 23.4 (SD = 3.7) years. Community-based nutrition has resulted in a statistically significant increase in levels of maternal knowledge of IFAS by 15.2% in the intervention group compared to 5.1% in the control group. Similarly, the intervention group had odds of developing a positive attitude toward IFA 5.6 (4.01, 7.85) times higher than the control group. Moreover, in this study, the odds of compliance towards IFA supplementation were 3.9 (2.67, 5.57) times higher among those who received nutrition education than those women who did not. CONCLUSION: This study revealed that community-based nutritional education can result in a significant change in knowledge, attitude, and compliance towards IFA supplementation and supports the literature suggesting the importance of the intervention to overcome the problem of poor compliance and its associated consequences.


Assuntos
Suplementos Nutricionais , Gestantes , Feminino , Gravidez , Humanos , Adulto Jovem , Adulto , Conhecimentos, Atitudes e Prática em Saúde , Etiópia , Ácido Fólico , Ferro , Cuidado Pré-Natal/métodos
7.
J Med Virol ; 94(9): 4554-4558, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35546445

RESUMO

In sub-Saharan Africa, the Human Herpesvirus 8 (HHV-8) is endemic but with disparities between regions and population studied. Although the virus remains mostly latent, there is some evidence that blood transfusion may represents one of the transmission way for this virus. Here, we evaluated HHV-8 seroprevalence among blood donors in Mali. This cross-sectional study recruited blood donors from the Blood Transfusion Center at Gabriel Touré Hospital, Bamako. Serum was used for the detection of latent HHV-8 immunoglobulin G directed against latent associated nuclear antigen 1 by an indirect immunofluorescence assay. Human immunodeficiency virus 1 (HIV-1), Hepatitis B Virus (HBV), HCV, and Treponema pallidum were also screened. HHV-8 seroprevalence was 10.4% in Malian blood donors. None of the sociodemographic characteristics were associated with HHV-8 infection, although there is a tendency of a higher HHV-8 seroprevalence among participants living in Bamako than those not living there. One individual had coinfection HHV-8/HBV, another HHV-8/HCV while another had HCV and T. pallidum. None has been tested positive for HIV infection. This intermediate seroprevalence in Malian blood donors suggests that the risk of HHV-8 transmission by transfusion should be considered. Further investigations are needed to assess impact of HHV-8 in polytransfused patients residing in an endemic area for this virus.


Assuntos
Infecções por HIV , Hepatite B , Hepatite C , Herpesvirus Humano 8 , Sífilis , Anticorpos Antivirais , Doadores de Sangue , Estudos Transversais , Vírus da Hepatite B , Hepatite C/epidemiologia , Humanos , Mali/epidemiologia , Estudos Soroepidemiológicos
8.
Appl Microbiol Biotechnol ; 106(2): 855-863, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34921327

RESUMO

The outbreak of goose gout disease caused by novel goose astrovirus type 1 (GAstV-1) has resulted in huge economic losses to the goose industry in China since 2017. However, little is known about the B cell epitopes in major antigen of GAstV-1 and the serological approach for detection of GAstV-1 is not available. In this study, three novel monoclonal antibodies (mAbs) against the ORF2 protein were first generated and designated as 3G6, 5H7, and 6C6, respectively. Epitope mapping revealed that mAb 3G6, 5H7, and 6C6 recognized 695AVRFEKGGHE704, 685EKALSAPQAG694, and 635DDDPLSDVTS644 in ORF2, respectively. Sequence alignments found that the three epitopes were highly conserved in GAstV-1 but not in other AAstV members. Moreover, a mAb-based sandwich ELISA for the detection of GAstV-1 was first developed using mAb 6C6. The sandwich ELISA only reacted with GAstV-1 but not with GAstV-2 and the other goose-associated viruses tested. The limit of the detection of the sandwich ELISA reaches 1.58 × 103 TCID50/mL of GAstV-1. Notably, mAb 6C6 could also efficiently react with the GAstV-1 in tissue frozen sections of the clinical infected goose through IFA. The mAbs generated in this study pave the way for further studying on the role of ORF2 in the infection and pathogenesis of GAstV, and the sandwich ELISA and the tissue frozen section-IFA approaches established here provide efficient and rapid serological diagnostic tools for detection of GAstV-1. KEY POINTS: • Three novel B cell epitopes were identified in ORF2 of GAstV-1. • mAb-based ELISA and IFA for detection of GAstV-1 were developed.


Assuntos
Avastrovirus , Gansos , Animais , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Epitopos de Linfócito B
9.
BMC Pregnancy Childbirth ; 22(1): 179, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241006

RESUMO

INTRODUCTION: Anemia in pregnancy is an important global public health problem. It is estimated that 38% of pregnant women worldwide are anemic. In Africa, literature from observational studies show 20% of maternal deaths are attributed to anemia. In Uganda, 50% of pregnant women have iron deficiency anaemia. The proportion of pregnant women receiving Iron-Folic acid (IFA) supplementation has improved. However, the number of IFA pills consumed is still low. We carried out a randomized controlled trial to determine the effect of dispensing blister and loose packaged IFA pills on adherence measured by count on next return visit and hemoglobin levels among pregnant women at two National Referral Hospitals in Kampala, Uganda. METHODS: This trial was conducted between April and October 2016. Nine hundred fifty pregnant women at ≤28 weeks were randomized to either the blister (intervention arm) or loose (control arm) packaged IFA. The participants completed the baseline measurements and received 30 pills of IFA at enrolment to swallow one pill per day. We assessed adherence by pill count and measured hemoglobin at four and 8 weeks. The results were presented using both intention-to-treat and per-protocol analysis. RESULTS: There were 474 participants in the control and 478 in the intervention arms. Adherence to IFA intake was similar in the two groups at 4th week (40.6 and 39.0%, p = 0.624) and 8th week (51.9 and 46.8%, p = 0.119). The mean hemoglobin level at 4 weeks was higher in the blister than in the loose packaging arms (11.9 + 1.1 g/dl and 11.8 + 1.3 g/dl, respectively; p = 0.02), however, similar at week 8 (12.1 + 1.2 and 12.0 + 1.3, respectively; p = 0.23). However, over the 8-week period blister packaging arm had a higher change in hemoglobin level compared to loose package (blister package 0.6 ± 1.0; loose packaging 0.2 ± 1.1; difference: 0.4 g/dL (95% CI: 0.24-0.51 g/dL); p = 0.001. There were no serious adverse events. CONCLUSIONS: Our results showed no effect of blister packaging on IFA adherence among pregnant women. However, our findings showed that blister packaged group had a higher hemoglobin increase compared to loose iron group. TRIAL REGISTRATION: No. PACTR201707002436264 (20 /07/ 2017).


Assuntos
Suplementos Nutricionais , Embalagem de Medicamentos/métodos , Ácido Fólico/administração & dosagem , Ferro da Dieta/administração & dosagem , Adesão à Medicação , Cuidado Pré-Natal , Adulto , Anemia Ferropriva/prevenção & controle , Feminino , Ácido Fólico/sangue , Humanos , Ferro da Dieta/sangue , Gravidez/sangue , Complicações Hematológicas na Gravidez/prevenção & controle , Comprimidos , Uganda
10.
Exp Parasitol ; 238: 108284, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35609626

RESUMO

Toxocariasis is caused by infection with the nematode species Toxocara canis and Toxocara cati. Serological methods using eggs, larvae and adult worms of Toxocara spp. as antigen have been used for the diagnosis of human toxocariasis. The current study aimed to evaluate indirect immunofluorescence assay (IFA) using embryonated eggs of Toxocara for diagnosis of human toxocariasis. A total of 58 sera including twenty sera from patients with toxocariasis, 20 from healthy persons and 18 from patients with other parasitic infections were collected and used for the study. The embryonated eggs of Toxocara were prepared as antigen. Indirect immunofluorescence assay was performed using the frozen section of uterus containing embryonated T. canis eggs and unembryonated T. cati eggs. All serum samples had a positive reaction using IFA. The eggs of Toxocara as antigen exposed to the serum samples of toxocariasis, other parasitic infections and healthy persons, followed by IFA gave a bright greenish-yellow fluorescence. A number of samples such as eggs of Toxocara, Toxascaris, Trichuris and strongyloides larvae, and adult worm of Ancylostoma exhibited the bright greenish-yellow autofluorescence under fluorescent microscope. IFA using cryocut of embryonated eggs of Toxocara cannot be used for the diagnosis of human toxocariasis due to the existence of autofluorescence of the unembryonated and embryonated eggs, the second stage larva and adult worms of Toxocara spp.


Assuntos
Toxocara canis , Toxocaríase , Animais , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Larva , Toxocara , Toxocaríase/parasitologia
11.
Foodborne Pathog Dis ; 19(6): 394-399, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35443790

RESUMO

The aim of this study was to assess the agreement between anti-Toxoplasma gondii IgG antibody detection in serum and filter paper (FP) blood spots using the indirect immunofluorescence antibody assay (IFA) and to evaluate the potential impact of the packed cell volume (PCV) on antibody detection in FPs. A pair of a serum and an FP sample was collected from 96 sows at various farms in Greece, with previously identified high seropositivity and/or risk factors associated with high seropositivity against T. gondii. The PCV value was determined using the microhematocrit method. IFA was used for the detection of antibodies against T. gondii. T. gondii-specific antibodies were detected in 45.8% serum samples and 41.6% FP samples showing almost perfect agreement. Detection in FP samples presented high sensitivity (87.1-92.8%) and excellent specificity (100%) when compared with detection in serum, regardless of the PCV values. The findings of this study support the reliability of FPs for the evaluation of the serological status of swine against T. gondii. FPs could be a good alternative sample type compared with serum for large-scale epidemiological studies.


Assuntos
Doenças dos Suínos , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários , Tamanho Celular , Feminino , Reprodutibilidade dos Testes , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/diagnóstico , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/epidemiologia
12.
Exp Appl Acarol ; 88(3-4): 371-386, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344862

RESUMO

From June 2013 to January 2014, blood sera samples and ticks were collected from domestic dogs and wild small mammals, and ticks from the vegetation in a preservation area of the Atlantic Forest biome (Turvo State Park), and the rural area surrounding the Park in Derrubadas municipality, state of Rio Grande do Sul, southern Brazil. Dogs were infested by Amblyomma ovale and Amblyomma aureolatum adult ticks, whereas small mammals were infested by immature stages of A. ovale, Amblyomma yucumense, Amblyomma brasiliense, Ixodes loricatus, and adults of I. loricatus. Ticks collected on vegetation were A. brasiliense, A. ovale, A. yucumense, Amblyomma incisum, and Haemaphysalis juxtakochi. Three Rickettsia species were molecularly detected in ticks: Rickettsia bellii in I. loricatus (also isolated through cell culture inoculation), Rickettsia amblyommatis in A. brasiliense, and Rickettsia rhipicephali in A. yucumense. The latter two are tick-rickettsia associations reported for the first time. Seroreactivity to Rickettsia antigens were detected in 33.5% (55/164) small mammals and 8.3% (3/36) canine sera. The present study reveals a richness of ticks and associated-rickettsiae in the largest Atlantic Forest Reserve of the state of Rio Grande do Sul, which is characterized by a rich fauna of wild mammals, typical of more preserved areas of this biome. Noteworthy, none of the detected Rickettsia species have been associated to human or animal diseases. This result contrasts to other areas of this biome in Brazil, which are endemic for tick-borne spotted fever caused by Rickettsia rickettsii or Rickettsia parkeri.


Assuntos
Carrapatos , Humanos , Cães , Animais , Brasil , Mamíferos
13.
BMC Genomics ; 22(1): 470, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34167474

RESUMO

BACKGROUND: Fusarium head blight (FHB) is a devastating disease of wheat worldwide. Resistance to FHB is quantitatively controlled by the combined effects of many small to medium effect QTL. Flowering traits, especially the extent of extruded anthers, are strongly associated with FHB resistance. RESULTS: To characterize the genetic basis of FHB resistance, we generated and analyzed phenotypic and gene expression data on the response to Fusarium graminearum (Fg) infection in 96 European winter wheat genotypes, including several lines containing introgressions from the highly resistant Asian cultivar Sumai3. The 96 lines represented a broad range in FHB resistance and were assigned to sub-groups based on their phenotypic FHB severity score. Comparative analyses were conducted to connect sub-group-specific expression profiles in response to Fg infection with FHB resistance level. Collectively, over 12,300 wheat genes were Fusarium responsive. The core set of genes induced in response to Fg was common across different resistance groups, indicating that the activation of basal defense response mechanisms was largely independent of the resistance level of the wheat line. Fg-induced genes tended to have higher expression levels in more susceptible genotypes. Compared to the more susceptible non-Sumai3 lines, the Sumai3-derivatives demonstrated higher constitutive expression of genes associated with cell wall and plant-type secondary cell wall biogenesis and higher constitutive and Fg-induced expression of genes involved in terpene metabolism. Gene expression analysis of the FHB QTL Qfhs.ifa-5A identified a constitutively expressed gene encoding a stress response NST1-like protein (TraesCS5A01G211300LC) as a candidate gene for FHB resistance. NST1 genes are key regulators of secondary cell wall biosynthesis in anther endothecium cells. Whether the stress response NST1-like gene affects anther extrusion, thereby affecting FHB resistance, needs further investigation. CONCLUSION: Induced and preexisting cell wall components and terpene metabolites contribute to resistance and limit fungal colonization early on. In contrast, excessive gene expression directs plant defense response towards programmed cell death which favors necrotrophic growth of the Fg pathogen and could thus lead to increased fungal colonization.


Assuntos
Fusarium , Resistência à Doença/genética , Perfilação da Expressão Gênica , Doenças das Plantas/genética , Triticum/genética
14.
J Clin Microbiol ; 59(6)2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-33731411

RESUMO

Bartonella spp., mostly Bartonella quintana and B. henselae, are a common cause of culture-negative endocarditis. Serology using immunofluorescence assay (IFA) and PCR performed on cardiac tissues are the mainstays of diagnosis. We developed an enzyme immunoassay (EIA) and a novel multiplex real-time PCR assay, utilizing Bartonella genus-specific, B. henselae-specific, and B. quintana-specific SimpleProbe probes, for diagnosis of Bartonella endocarditis. We aimed to evaluate the performance of these assays. Thirty-seven patients with definite endocarditis, 18 with B. henselae, 18 with B. quintana, and 1 with B. koehlerae, were studied. Diagnosis was confirmed by conventional PCR and DNA sequencing of surgical cardiac specimens. Similar to the case with IFA, anti-Bartonella IgG titers of ≥1:800 were found in 94% of patients by EIA; cross-reactivity between B. henselae and B. quintana precluded species-specific serodiagnosis, and frequent (41%) but low-titer cross-reactivity between Coxiella burnetii antibodies and B. henselae antigen was found in patients with Q fever endocarditis. Low-titer (1:100) cross-reactivity was uncommonly found also in patients with brucellosis and culture-positive endocarditis, particularly Enterococcus faecalis endocarditis. Real-time PCR performed on explanted heart valves/vegetations was in complete agreement with results of sequence-based diagnosis with characteristic melting curves. The genus-specific probe identified five additional endocarditis-associated Bartonella spp. at the genus level. In conclusion, EIA coupled with a novel real-time PCR assay can play an important role in Bartonella endocarditis diagnosis and expand the diagnostic arsenal at the disposal of the clinical microbiologist. Since serology remains a major diagnostic tool, recognizing its pitfalls is essential to avoid incorrect diagnosis.


Assuntos
Infecções por Bartonella , Bartonella henselae , Bartonella quintana , Bartonella , Endocardite , Anticorpos Antibacterianos , Bartonella/genética , Infecções por Bartonella/diagnóstico , Bartonella henselae/genética , Bartonella quintana/genética , Humanos , Técnicas Imunoenzimáticas , Reação em Cadeia da Polimerase em Tempo Real , Testes Sorológicos
15.
Sens Actuators B Chem ; 329: 129214, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36568647

RESUMO

This review reports the recent advances in surface-enhanced Raman scattering (SERS)-based lateral flow assay (LFA) platforms for the diagnosis of infectious diseases. As observed through the recent infection outbreaks of COVID-19 worldwide, a timely diagnosis of the disease is critical for preventing the spread of a disease and to ensure epidemic preparedness. In this regard, an innovative point-of-care diagnostic method is essential. Recently, SERS-based assay platforms have received increasing attention in medical communities owing to their high sensitivity and multiplex detection capability. In contrast, LFAs provide a user-friendly and easily accessible sensing platform. Thus, the combination of LFAs with a SERS detection system provides a new diagnostic modality for accurate and rapid diagnoses of infectious diseases. In this context, we briefly discuss the recent application of LFA platforms for the POC diagnosis of SARS-CoV-2. Thereafter, we focus on the recent advances in SERS-based LFA platforms for the early diagnosis of infectious diseases and their applicability for the rapid diagnosis of SARS-CoV-2. Finally, the key issues that need to be addressed to accelerate the clinical translation of SERS-based LFA platforms from the research laboratory to the bedside are discussed.

16.
Exp Appl Acarol ; 83(4): 555-573, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33779896

RESUMO

Rondônia is the only state in the North Region of Brazil to have registered confirmed cases of Brazilian Spotted Fever (BSF). The present study investigated the epidemiological cycle of Rickettsia spp. by surveying free-living ixodofauna and tick parasitism of dogs in the municipality of Porto Velho, Rondônia State. Ticks and dogs were tested for the presence of Rickettsia spp. DNA and dog serum was tested for reactivity to anti-Rickettsia spp. antibodies. Tick collection and dog blood sampling were performed in peri-urban and rural environments at 11 locations. Eight free-living Amblyomma species and one Haemaphysalis species were collected: A. scalpturatum, A. naponense, A. oblongoguttatum, A. coelebs, A. latepunctatum, A. pacae, A. ovale, Amblyomma sp., and H. juxtakochi. Three tick species were found parasitizing dogs: Rhipicephalus sanguineus sensu lato, A. oblongoguttatum and A. ovale. Molecular analysis did not identify the presence of the gltA gene fragment in any tick specimen. Results from an indirect immunofluorescent assay (IFA) showed that 20.8% of peri-urban and 15.4% of rural dog sera exhibited reactivity to Rickettsia rhipicephali, Rickettsia amblyommatis, Rickettsia bellii and Rickettsia parkeri antigens. Antibody prevalence in dogs was 16.4%. This study is the first to describe the prevalence of Rickettsia spp. infection in dogs from Porto Velho municipality. Our findings enhance current knowledge of Rickettsia spp. circulation in the Western Amazon.


Assuntos
Doenças do Cão , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Carrapatos , Animais , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Cães
17.
Molecules ; 26(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069351

RESUMO

Dengue virus (DENV), a member of the family Flaviviridae, is a threat for global health as it infects more than 100 million people yearly. Approved antiviral therapies or vaccines for the treatment or prevention of DENV infections are not available. In the present study, natural compounds were screened for their antiviral activity against DENV by in vitro cell line-based assay. α-Mangostin, a xanthanoid, was observed to exert antiviral activity against DENV-2 under pre-, co- and post-treatment testing conditions. The antiviral activity was determined by foci forming unit (FFU) assay, quantitative RT-PCR and cell-based immunofluorescence assay (IFA). A complete inhibition of DENV-2 was observed at 8 µM under the co-treatment condition. The possible inhibitory mechanism of α-Mangostin was also determined by docking studies. The molecular docking experiments indicate that α-Mangostin can interact with multiple DENV protein targets such as the NS5 methyltransferase, NS2B-NS3 protease and the glycoprotein E. The in vitro and in silico findings suggest that α-Mangostin possesses the ability to suppress DENV-2 production at different stages of its replication cycle and might act as a prophylactic/therapeutic agent against DENV-2.


Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Xantonas/farmacologia , Animais , Antivirais/química , Chlorocebus aethiops , Imunofluorescência , Humanos , Técnicas In Vitro , Simulação de Acoplamento Molecular , Células Vero , Xantonas/química
18.
J Med Virol ; 92(10): 2243-2247, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32510168

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological assays are urgently needed for rapid diagnosis, contact tracing, and for epidemiological studies. So far, there is limited data on how commercially available tests perform with real patient samples, and if positive tested samples show neutralizing abilities. Focusing on IgG antibodies, we demonstrate the performance of two enzyme-linked immunosorbent assay (ELISA) assays (Euroimmun SARS-CoV-2 IgG and Vircell COVID-19 ELISA IgG) in comparison to one lateral flow assay (FaStep COVID-19 IgG/IgM Rapid Test Device) and two in-house developed assays (immunofluorescence assay [IFA] and plaque reduction neutralization test [PRNT]). We tested follow up serum/plasma samples of individuals polymerase chain reaction-diagnosed with COVID-19. Most of the SARS-CoV-2 samples were from individuals with moderate to the severe clinical course, who required an in-patient hospital stay. For all examined assays, the sensitivity ranged from 58.8 to 76.5% for the early phase of infection (days 5-9) and from 93.8% to 100% for the later period (days 10-18).


Assuntos
Anticorpos Antivirais/sangue , COVID-19/diagnóstico , Imunoglobulina G/sangue , SARS-CoV-2/imunologia , Adulto , COVID-19/sangue , COVID-19/imunologia , COVID-19/virologia , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Técnica Indireta de Fluorescência para Anticorpo/normas , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização/normas , SARS-CoV-2/patogenicidade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Fatores de Tempo
19.
J Eukaryot Microbiol ; 67(6): 671-677, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32702183

RESUMO

Microsporidia are a group of obligate intracellular parasites causing significant disease in human beings and economically important animals. Though a few spore wall proteins (SWPs) have now been identified in these intriguing species, the information on SWPs remains too little to elucidate the spore wall formation mechanisms of microsporidia. It has been well described that numerous proteins with tandem repeats tend to be localized on the cell wall of fungi and parasites. Previously, by scanning the proteins with tandem repeats in microsporidian Nosema bombycis, we obtained 83 candidate SWPs based on whether those proteins possess a signal peptide and/or transmembrane domain. Here, we further characterized a candidate protein (EOB13250) with three tandem repeats in the N-terminal region and a transmembrane domain in C-terminus of N. bombycis. Sequence analysis showed that the tandem repeat domain of EOB13250 was species-specific for this parasite. RT-PCR indicated that the expression of the gene encoding this protein started on the fourth day postinfection. After cloned and expressed in Escherichia coli, a polyclone antibody against the recombinant EOB13250 protein was prepared. Western blotting demonstrated this protein exist in N. bombycis. Immunofluorescence analysis (IFA) and immunoelectron microscopy analysis (IEM) further provided evidence that EOB13250 was an endospore wall protein. These results together suggested that EOB13250 was a novel spore wall protein of N. bombycis. This study provides a further enrichment of the number of identified spore wall proteins in microsporidia and advances our understanding of the spore wall formation mechanism in these obligate unicellular parasites.


Assuntos
Nosema/genética , Nosema/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Sequência de Aminoácidos , Animais , Parede Celular/metabolismo , DNA de Protozoário , Nosema/ultraestrutura , Esporos de Protozoários/metabolismo , Sequências de Repetição em Tandem
20.
Klin Lab Diagn ; 65(2): 90-94, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32159305

RESUMO

A research objective - to study the possibility of using the ELISA Anti-K enzyme immunoassay system to evaluate anti-pertussis immunity. А comparative assessment of the content of co-crank antibodies in the blood serum of adults, pregnant women and children 6 years old in the agglutination test, in the test system "Anti-K ELISA" and test systems of foreign production was carried out. The "Anti-K" IFA test system makes it possible to detect the level of specific antibodies to both the whole cell and cell-free pertussis component of the vaccine at any stage of the vaccination cycle. This diagnostic test can be used to determine the tactics of immunization, and to assess population immunity.


Assuntos
Anticorpos Antibacterianos/análise , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Coqueluche/imunologia , Adulto , Testes de Aglutinação , Criança , Feminino , Humanos , Imunidade , Vacina contra Coqueluche , Gravidez , Vacinação
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