Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 104
Filtrar
1.
PLoS Genet ; 18(7): e1010340, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35905103

RESUMO

Puf5, a Puf-family RNA-binding protein, binds to 3´ untranslated region of target mRNAs and negatively regulates their expression in Saccharomyces cerevisiae. The puf5Δ mutant shows pleiotropic phenotypes including a weakened cell wall, a temperature-sensitive growth, and a shorter lifespan. To further analyze a role of Puf5 in cell growth, we searched for a multicopy suppressor of the temperature-sensitive growth of the puf5Δ mutant in this study. We found that overexpression of CLB2 encoding B-type cyclin suppressed the temperature-sensitive growth of the puf5Δ mutant. The puf5Δ clb2Δ double mutant displayed a severe growth defect, suggesting that Puf5 positively regulates the expression of a redundant factor with Clb2 in cell cycle progression. We found that expression of CLB1 encoding a redundant B-type cyclin was decreased in the puf5Δ mutant, and that this decrease of the CLB1 expression contributed to the growth defect of the puf5Δ clb2Δ double mutant. Since Puf5 is a negative regulator of the gene expression, we hypothesized that Puf5 negatively regulates the expression of a factor that represses CLB1 expression. We found such a repressor, Ixr1, which is an HMGB (High Mobility Group box B) protein. Deletion of IXR1 restored the decreased expression of CLB1 caused by the puf5Δ mutation and suppressed the growth defect of the puf5Δ clb2Δ double mutant. The expression of IXR1 was negatively regulated by Puf5 in an IXR1 3´ UTR-dependent manner. Our results suggest that IXR1 mRNA is a physiologically important target of Puf5, and that Puf5 and Ixr1 contribute to the cell cycle progression through the regulation of the cell cycle-specific expression of CLB1.


Assuntos
Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae , Ciclo Celular/genética , Ciclinas/genética , Ciclinas/metabolismo , Proteínas de Ligação a DNA/genética , Regulação Fúngica da Expressão Gênica , Proteínas HMGB/genética , Proteínas de Grupo de Alta Mobilidade/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
2.
J Clin Biochem Nutr ; 72(1): 61-67, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36777082

RESUMO

Fructose is associated with hyperuricemia and gout development. Focusing on fructose and fructose-containing disaccharides, we investigated the effects of three different types of carbohydrates (fructose, sucrose, and isomaltulose) on uric acid metabolism and gene expression profiling in peripheral white blood cells. In a randomized crossover study, ten healthy participants ingested test drinks of fructose, sucrose, and isomaltulose, each containing 25 g of fructose. Plasma glucose, serum and urine uric acid, and xanthine/hypoxanthine concentrations were measured. Microarray analysis in peripheral white blood cells and real-time reverse transcription polymerase chain reaction were examined at 0 and 120 in after the intake of test drinks. Serum uric acid concentrations for group fructose were significantly higher than group sucrose at 30-120 min and were significantly higher than those for group isomaltulose at 30-240 min. Several genes involved in the "nuclear factor-kappa B signaling pathway" were markedly changed in group fructose. No significant differences in the mRNA expression levels of tumor necrosis factor, nuclear factor-kappa B, interleukin-1ß, and interleukin-18 were noted. This study indicated that fructose intake (monosaccharide) elevated serum uric acid concentrations compared with disaccharide intake. Differences in the quality of carbohydrates might reduce the rapid increase of postprandial serum uric acid concentrations.

3.
Mod Rheumatol ; 33(1): 88-95, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35134981

RESUMO

OBJECTIVE: To investigate the influence of nutritional status on severe infection complications in patients with rheumatoid arthritis (RA). METHODS: This retrospective cohort study on 2108 patients with RA evaluated the prognostic nutritional index (PNI) as an index of nutritional status. Patients were classified into the high or low PNI group according to the cutoff PNI value (45.0). Based on propensity score matching analysis, 360 patients in each group were selected for comparing the incidence of serious infection, clinical findings, and PNI scores. RESULTS: The incidence of infection was significantly higher in the low PNI group than in the high PNI group (p < 0.001). The occurrence rate of infectious complication at 104 weeks was significantly higher in the low PNI (<45.0) group than in the high PNI group (p < 0.001). The incidence of infection was particularly high in elderly patients (≥65 years) with a low PNI, but the incidence in elderly patients with a high PNI was similar to that in nonelderly patients with a high PNI. CONCLUSIONS: Patients with RA and malnutrition had a higher incidence of severe infection; thus, evaluating and managing nutritional status is necessary for the appropriate and safe treatment of elderly patients with RA.


Assuntos
Artrite Reumatoide , Avaliação Nutricional , Humanos , Idoso , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Artrite Reumatoide/complicações
4.
Contact Dermatitis ; 84(2): 103-108, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32909284

RESUMO

BACKGROUND: The clinical characteristics of patients with allergic contact dermatitis (ACD) due to a skin adhesive containing 2-octyl cyanoacrylate, Dermabond®, have not yet been elucidated. OBJECTIVE: To investigate the clinical characteristics of patients with ACD caused by Dermabond® application. METHODS: In this retrospective study, 577 patch tested patients were included. We identified patients with positive patch test results for Dermabond® and evaluated their results concerning (meth)acrylates and ethyl cyanoacrylate adhesive. RESULTS: Nine patients had positive patch test results to Dermabond®; six had developed secondary generalization.The mean time between Dermabond® application and ACD onset was 34 days (range, 27-44) in six patients with ACD after the first use, whereas, in the other three patients, it was 5.6 days (range, 4-8) after the second use. The time was significantly different between the two groups (P < .01). Positive reactions to ethyl cyanoacrylate adhesive (Aron Alpha) occurred in seven of nine patients, to ethyl cyanoacrylate 10% pet. in four of eight patients tested, and to 2-hydroxyethyl methacrylate in one of eight patients tested. CONCLUSIONS: Dermabond®-induced ACD is apparently characterized by a high prevalence of primary sensitization at first exposure to Dermabond®, secondary generalization is frequent, and most patients show cross-reactivity to ethyl cyanoacrylate.


Assuntos
Cianoacrilatos/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Adesivos Teciduais/efeitos adversos , Adulto , Reações Cruzadas , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Complicações Pós-Operatórias/diagnóstico , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
5.
Int J Mol Sci ; 22(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374403

RESUMO

Both fluorescent and luminescent observation are widely used to examine real-time gene expression patterns in living organisms. Several fluuorescent and luminescent proteins with specific optical properties have been developed and applied for simultaneous, multi-color observation of more than two gene expression profiles. Compared to fluorescent proteins, however, the application of multi-color luminescent imaging in living organisms is still limited. In this study, we introduced two-color luciferases into the soil nematode C. elegans and performed simultaneous analysis of two gene expression profiles. Using a green-emitting luciferase Eluc (emerald luciferase) and red-emitting luciferase SLR (stable luciferase red), the expression patterns of two genes were simultaneously observed in single animals from embryonic to adult stages over its whole life span. In addition, dual gene activities were observed at the single embryo level, with the simultaneous observation of morphological changes. These are the first application of a two-color luciferase system into a whole animal and suggest that precise relationship of expression patterns of multiple genes of interest can be analyzed over the whole life of the animal, dependent on the changes in genetic and/or environmental conditions.


Assuntos
Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Perfilação da Expressão Gênica , Luciferases/metabolismo , Animais , Animais Geneticamente Modificados , Cor , Corantes Fluorescentes , Regulação da Expressão Gênica , Luminescência , Medições Luminescentes/métodos , Proteínas Luminescentes/genética , Regiões Promotoras Genéticas
7.
Biol Blood Marrow Transplant ; 24(9): 1896-1900, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29803752

RESUMO

Sinusoidal obstruction syndrome (SOS)/hepatic veno-occlusive disease (VOD) is a well-documented complication after hematopoietic stem cell transplantation (HSCT). Transabdominal ultrasonography (US) enables the visualization of blood flow abnormalities and is therefore useful for the diagnosis of SOS/VOD. We herein prospectively evaluated accuracy of a novel US diagnostic scoring system of SOS/VOD based on US findings. We carried out US in 106 patients on day 14 and when SOS/VOD was suspected after allogeneic HSCT. Among 106 patients, 10 patients (9.4%) were diagnosed as SOS/VOD by Baltimore or Seattle criteria. According to univariate analysis of 17 US findings (US-17 screening), we established a novel scoring system (HokUS-10) consisting of 10 parameters, such as gallbladder wall thickening, ascites, and blood flow signal in the paraumbilical vein. The sensitivity and specificity were 100% and 95.8%, respectively. Diagnostic performance of the HokUS-10 was significantly better than US-17 screening. In 4 of 10 patients US detection of SOS/VOD preceded to clinical diagnosis. The HokUS-10 scoring system is useful in the diagnosis of SOS/VOD; however, our results should be validated in other cohorts.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hepatopatia Veno-Oclusiva/diagnóstico por imagem , Hepatopatia Veno-Oclusiva/etiologia , Condicionamento Pré-Transplante/efeitos adversos , Ultrassonografia/métodos , Adulto , Idoso , Feminino , Hepatopatia Veno-Oclusiva/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
8.
Zoolog Sci ; 34(4): 261-266, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28770683

RESUMO

Recent experimental studies involving the manipulation of sexual traits have demonstrated that sexual trait expression feeds back to testosterone levels, perhaps via social interactions, reinforcing the linkage between sexual trait expression and testosterone levels during the mating period. However, information on this reinforcement under the natural variation of sexual traits remains limited. Using Japanese barn swallows, Hirundo rustica gutturalis, in which extra-pair paternity is quite rare (< 3%), we studied the relationship between plasma testosterone level and a male sexual trait, throat patch size, during the mating and incubation periods. Given the importance of social interaction, we predicted that this relationship should be intense during the mating period, but not the incubation period, due to reduced social interaction during the latter. We found low plasma testosterone levels during the incubation period compared with those in the mating period, and plasma testosterone levels were significantly positively related to throat patch area during the mating period, but not the incubation period. Similar relationships were found in another sexual trait, the size of white tail spots. During the incubation period, body condition, instead of male sexual trait expression, was negatively related to plasma testosterone level, indicating that an intrinsic link, rather than reinforcement, is important during this period. These relationships are consistent with the hypothesis that social interaction reinforces the relationship between sexual traits and plasma testosterone levels. The current study provides evidence for a highly variable relationship between testosterone and ornamentation across breeding periods in the natural variation of sexual traits.


Assuntos
Comportamento de Nidação , Comportamento Sexual Animal , Andorinhas/fisiologia , Testosterona/sangue , Animais , Japão , Masculino , Andorinhas/sangue
9.
Appl Microbiol Biotechnol ; 101(16): 6399-6408, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28688044

RESUMO

Aspergillus niger α-glucosidase (ANG), a member of glycoside hydrolase family 31, catalyzes hydrolysis of α-glucosidic linkages at the non-reducing end. In the presence of high concentrations of maltose, the enzyme also catalyzes the formation of α-(1→6)-glucosyl products by transglucosylation and it is used for production of the industrially useful panose and isomaltooligosaccharides. The initial transglucosylation by wild-type ANG in the presence of 100 mM maltose [Glc(α1-4)Glc] yields both α-(1→6)- and α-(1→4)-glucosidic linkages, the latter constituting ~25% of the total transfer reaction product. The maltotriose [Glc(α1-4)Glc(α1-4)Glc], α-(1→4)-glucosyl product disappears quickly, whereas the α-(1→6)-glucosyl products panose [Glc(α1-6)Glc(α1-4)Glc], isomaltose [Glc(α1-6)Glc], and isomaltotriose [Glc(α1-6)Glc(α1-6)Glc] accumulate. To modify the transglucosylation properties of ANG, residue Asn694, which was predicted to be involved in formation of the plus subsites of ANG, was replaced with Ala, Leu, Phe, and Trp. Except for N694A, the mutations enhanced the initial velocity of the α-(1→4)-transfer reaction to produce maltotriose, which was then degraded at a rate similar to that by wild-type ANG. With increasing reaction time, N694F and N694W mutations led to the accumulation of larger amounts of isomaltose and isomaltotriose than achieved with the wild-type enzyme. In the final stage of the reaction, the major product was panose (N694A and N694L) or isomaltose (N694F and N694W).


Assuntos
Aspergillus niger/genética , Aspergillus niger/metabolismo , Mutação , alfa-Glucosidases/química , alfa-Glucosidases/genética , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/enzimologia , Glucanos/metabolismo , Glucanos/farmacologia , Concentração de Íons de Hidrogênio , Hidrólise , Isomaltose/metabolismo , Cinética , Maltose/metabolismo , Maltose/farmacologia , Mutagênese Sítio-Dirigida , Especificidade por Substrato , Trissacarídeos/metabolismo , alfa-Glucosidases/metabolismo
10.
Pediatr Int ; 59(2): 154-158, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27706892

RESUMO

BACKGROUND: Guidelines recommend avoiding excessive oxygen during neonatal resuscitation. Recent studies have suggested that oxygen titration can be achieved using a self-inflating bag, but data on the effectiveness of resuscitators used in neonatal ventilation are scarce, The aim of this study was therefore to determine the amount of oxygen delivered using several brands of neonatal self-inflating resuscitation bags without reservoirs under different conditions with regard to oxygen flow rate, ventilation rate (VR), peak inspiratory pressure (PIP) range, and test lung compliance. METHODS: Oxygen concentration was measured under a variety of conditions. Combinations of oxygen flow rate (10, 5.0, 3.0 and 1.0 L/min), VR (40, 60 inflations/min), PIP range (20-25 cmH2 O, 35-40 cmH2 O), and test lung compliance (0.6, 1.0, 3.0, and 5.0 mL/cmH2 O) were examined using six kinds of self-inflating bag. RESULTS: Delivered oxygen concentration varied widely (30.1-96.7%) and had a significant positive correlation with gas flow rate in all of the bags. Delivered oxygen concentration was also negatively correlated with PIP in all of the bags and with VR in some of them. Test lung compliance did not affect delivered oxygen concentration. CONCLUSION: The use of neonatal resuscitation self-inflating bags without reservoirs resulted in different delivered oxygen concentrations depending on gas flow rate, VR, PIP, and manufacturer, but not on lung compliance. This suggests that targeted oxygen concentrations could be delivered, even in lungs with decreased compliance, during resuscitation.


Assuntos
Oxigenoterapia/instrumentação , Oxigênio/administração & dosagem , Respiração com Pressão Positiva/instrumentação , Humanos , Técnicas In Vitro , Recém-Nascido , Complacência Pulmonar , Oxigenoterapia/métodos , Respiração com Pressão Positiva/métodos
11.
Korean J Parasitol ; 54(4): 543-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27658609

RESUMO

In the present study, we report on the occurrence of paramphistomes, Fischoederius cobboldi and Paramphistomum epiclitum, in Lao PDR with the basis of molecular data. Parasite materials were collected from bovines bred in Ban Lahanam area, Savannakhet Province, Lao PDR at Lahanam public market. Morphological observations indicated 2 different species of paramphistomes. The mitochondrial gene cox1 of the specimens was successfully amplified by PCR and DNA sequencing was carried out for diagnosis of 11 specimens. Pairwise alignment of cox1 sequences were performed and confirmed F. cobboldi and P. epiclitum infecting bovines in Laos. Although there were many limiting points, as the small number of worm samples, and the restricted access of the animal host materials, we confirmed for the first time that 2 species of paramphistomes, F. cobboldi and P. epiclitum, are distributed in Lao PDR. More studies are needed to confirm the paramphistome species present in Savannakhet and its hosts to clear the natural history of these parasites of ruminants in the region and measure the impact of this parasite infection in the life and health of the local people.


Assuntos
Parasitologia de Alimentos , Paramphistomatidae/isolamento & purificação , Rúmen/parasitologia , Animais , Bovinos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Laos , Microscopia , Paramphistomatidae/anatomia & histologia , Paramphistomatidae/classificação , Paramphistomatidae/genética , Análise de Sequência de DNA
12.
Clin Transplant ; 29(8): 697-704, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26009803

RESUMO

Gastrointestinal graft-versus-host disease (GI-GVHD) is a major and life-threatening complication of hematopoietic stem cell transplantation (HSCT). This study evaluated the efficacy of ultrasonography (US) for assessing and monitoring GI-GVHD. GI tract was evaluated by US in 81 patients. US findings were positive in 43 patients, including 11 false positive, and negative in 38 patients. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of US for the diagnosis of GI-GVHD were 100%, 78%, 74%, 100%, and 86%, respectively. Diffuse wall thickening of the ileum was the most frequent finding in patients with GI-GVHD. Severity of GI-GVHD was correlated with the thickness of internal low echoic layer of the wall, the echogenicity of mesenteric fat tissue, and the intensity of Doppler signaling. We classified US findings of GI-GVHD into four US grades. There was a significant correlation between clinical stage of GI-GVHD and the US grade. These ultrasonographic abnormalities were improved with clinical improvement of GI-GVHD upon treatment. Thus, US is an effective and efficient non-invasive means of identifying the extent and severity of GI-GVHD and monitoring response to treatment.


Assuntos
Gastroenteropatias/diagnóstico por imagem , Rejeição de Enxerto/diagnóstico por imagem , Doença Enxerto-Hospedeiro/diagnóstico por imagem , Doenças Hematológicas/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Ultrassonografia/métodos , Adulto , Idoso , Feminino , Seguimentos , Gastroenteropatias/etiologia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Doença Enxerto-Hospedeiro/etiologia , Doenças Hematológicas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
13.
Biol Chem ; 395(6): 641-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24526609

RESUMO

A high homocysteine (Hcy) level is a risk factor for atherosclerosis. Hcy can be added to proteins through a process known as N-homocysteinylation. This is thought to be a potential cause of atherosclerosis induction. We previously reported that N-homocysteinylated apolipoprotein A-I (N-Hcy-apoA-I) was identified in normal human plasma. In this study, the effect of N-homocysteinylation on the functions of apoA-I was examined. A kinetic study using dimyristoyl phosphatidylcholine (DMPC) liposomes indicated that N-Hcy-apoA-I showed increased lipid-binding activity compared to wild-type apoA-I. Two reconstituted high-density lipoprotein (rHDL) particles of different sizes (approximately 8.2 nm and 7.6 nm in diameter) were produced by mixing apoA-I and 1-palmitoyl-2-oleoyl phosphatidylcholine (POPC). However, an increased ratio of large to small particles was found in rHDL prepared with N-Hcy-apoA-I. The normal apoA-I antioxidant ability, estimated by the suppression of conjugated diene formation in low-density lipoprotein (LDL) induced by copper sulfate oxidation, was considerably impaired when using N-Hcy-apoA-I. Although N-Hcy-apoA-I functioned as an oxidant, no significant difference was observed in the cholesterol efflux capacity from THP-1 macrophages between wild-type apoA-I and N-Hcy-apoA-I. These results suggest that N-Hcy-apoA-I might be proatherogenic due to its oxidative behavior but not an attenuation of cholesterol efflux capacity.


Assuntos
Antioxidantes/metabolismo , Apolipoproteína A-I/metabolismo , Colesterol/metabolismo , Humanos , Relação Estrutura-Atividade
14.
Malar J ; 13: 373, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25239687

RESUMO

BACKGROUND: Diagnostic techniques based on PCR for the detection of Plasmodium DNA can be highly sensitive and specific. The vast majority of these techniques rely, however, on the invasive sampling of blood from infected hosts. There is, currently, considerable interest in the possibility of using body fluids other than blood as sources of parasite DNA for PCR diagnosis. METHODS: Urine and faeces were obtained from a Plasmodium knowlesi infected-Japanese macaque (Macaca fuscata) over the course of an experimentally induced infection. P. knowlesi DNA (PkDNA) extracted from urine and faeces were monitored by nested PCR targeting the P. knowlesi specific cytochrome b (cytb) gene. RESULTS: Urinary PkDNA was detected on day 2, but was not amplified using DNA templates extracted from the samples on day 4, day 5 and day 6. Subsequently, urinary PkDNA was detected from day 7 until day 11, and from day 20 until day 30. PkDNA in faeces was detected from day 7 until day 11, and from day 20 until day 37. Moreover, real-time quantitative PCR showed a remarkable increase in the amount of urinary PkDNA following anti-malarial treatment. This might have been due to the release of a large amount of PkDNA from the degraded parasites as a result of the anti-malarial treatment, leading to excretion of PkDNA in the urine. CONCLUSIONS: The cytb-PCR system using urine and faecal samples is of potential use in molecular epidemiological surveys of malaria. In particular, monkey faecal samples could be useful for the detection of zoonotic primate malaria in its natural hosts.


Assuntos
DNA de Protozoário/urina , Fezes/química , Macaca/urina , Malária/parasitologia , Malária/urina , Plasmodium knowlesi/genética , Animais , DNA de Protozoário/análise , Modelos Animais de Doenças , Feminino , Malária/metabolismo , Malária/fisiopatologia , Microscopia , Técnicas de Diagnóstico Molecular , Parasitologia , Reação em Cadeia da Polimerase
17.
Anal Chim Acta ; 1303: 342439, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38609254

RESUMO

Advanced biopharmaceutical manufacturing requires novel process analytical technologies for the rapid and sensitive assessment of the higher-order structures of therapeutic proteins. However, conventional physicochemical analyses of denatured proteins have limitations in terms of sensitivity, throughput, analytical resolution, and real-time monitoring capacity. Although probe-based sensing can overcome these limitations, typical non-specific probes lack analytical resolution and provide little to no information regarding which parts of the protein structure have been collapsed. To meet these analytical demands, we generated biosensing probes derived from artificial proteins that could specifically recognize the higher-order structural changes in antibodies at the protein domain level. Biopanning of phage-displayed protein libraries generated artificial proteins that bound to a denatured antibody domain, but not its natively folded structure, with nanomolar affinity. The protein probes not only recognized the higher-order structural changes in intact IgGs but also distinguished between the denatured antibody domains. These domain-specific probes were used to generate response contour plots to visualize the antibody denaturation caused by various process parameters, such as pH, temperature, and holding time for acid elution and virus inactivation. These protein probes can be combined with established analytical techniques, such as surface plasmon resonance for real-time monitoring or plate-based assays for high-throughput analysis, to aid in the development of new analytical technologies for the process optimization and monitoring of antibody manufacturing.


Assuntos
Anticorpos , Produtos Biológicos , Controle de Qualidade , Domínios Proteicos , Técnicas de Visualização da Superfície Celular
18.
Parasit Vectors ; 17(1): 80, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383404

RESUMO

BACKGROUND: Opisthorchis viverrini infection is traditionally diagnosed using the Kato-Katz method and formalin ethyl-acetate concentration technique. However, the limited sensitivity and specificity of these techniques have prompted the exploration of various molecular approaches, such as conventional polymerase chain reaction (PCR) and real-time PCR, to detect O. viverrini infection. Recently, a novel technique known as recombinase polymerase amplification (RPA)-clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) (RPA-CRISPR/Cas) assay was developed as a point-of-care tool for the detection of various pathogens, including viruses and bacteria such as severe acute respiratory syndrome coronavirus 2 and Mycobacterium tuberculosis. This technology has demonstrated high sensitivity and specificity. Therefore, we developed and used the RPA-CRISPR/Cas assay to detect O. viverrini infection in field-collected human feces. METHODS: To detect O. viverrini infection in fecal samples, we developed a CRISPR/Cas12a (RNA-guided endonuclease) system combined with RPA (Ov-RPA-CRISPR/Cas12a). Several fecal samples, both helminth-positive and helminth-negative, were used for the development and optimization of amplification conditions, CRISPR/Cas detection conditions, detection limits, and specificity of the RPA-CRISPR/Cas12a assay for detecting O. viverrini infection. The detection results were determined using a real-time PCR system based on fluorescence values. Additionally, as the reporter was labeled with fluorescein, the detection results were visually inspected using an ultraviolet (UV) transilluminator. A receiver operating characteristic curve (ROC) was used to determine the optimal cutoff value for fluorescence detection. The diagnostic performance, including sensitivity and specificity, of the Ov-RPA-CRISPR/Cas12a assay was evaluated on the basis of comparison with standard methods. RESULTS: The Ov-RPA-CRISPR/Cas12a assay exhibited high specificity for detecting O. viverrini DNA. On the basis of the detection limit, the assay could detect O. viverrini DNA at concentrations as low as 10-1 ng using the real-time PCR system. However, in this method, visual inspection under UV light required a minimum concentration of 1 ng. To validate the Ov-RPA-CRISPR/Cas12a assay, 121 field-collected fecal samples were analyzed. Microscopic examination revealed that 29 samples were positive for O. viverrini-like eggs. Of these, 18 were confirmed as true positives on the basis of the Ov-RPA-CRISPR/Cas12a assay and microscopic examination, whereas 11 samples were determined as positive solely via microscopic examination, indicating the possibility of other minute intestinal fluke infections. CONCLUSIONS: The Ov-RPA-CRISPR/Cas12a assay developed in this study can successfully detect O. viverrini infection in field-collected feces. Due to the high specificity of the assay reported in this study, it can be used as an alternative approach to confirm O. viverrini infection, marking an initial step in the development of point-of-care diagnosis.


Assuntos
Opistorquíase , Opisthorchis , Animais , Humanos , Opisthorchis/genética , Sistemas CRISPR-Cas , Recombinases/genética , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase em Tempo Real , Fezes , DNA
19.
PLoS One ; 19(3): e0298656, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478554

RESUMO

Ixodid ticks, such as Ixodes ovatus and Haemaphysalis flava, are important vectors of tick-borne diseases in Japan, such as Japanese spotted fever caused by Rickettsia japonica. This study describes the Rickettsia infection rates influenced by the population genetic structure of I.ovatus and H. flava along an altitudinal gradient. A total of 346 adult I. ovatus and 243 H. flava were analyzed for the presence of Rickettsia by nested PCR targeting the 17kDA, gltA, rOmpA, and rOmpB genes. The population genetic structure was analyzed utilizing the mitochondrial cytochrome oxidase 1 (cox1) marker. The Rickettsia infection rates were 13.26% in I. ovatus and 6.17% in H. flava. For I. ovatus, the global FST value revealed significant genetic differentiation among the different populations, whereas H. flava showed non-significant genetic differentiation. The cox1 I. ovatus cluster dendrogram showed two cluster groups, while the haplotype network and phylogenetic tree showed three genetic groups. A significant difference was observed in Rickettsia infection rates and mean altitude per group between the two cluster groups and the three genetic groups identified within I. ovatus. No significant differences were found in the mean altitude or Rickettsia infection rates of H. flava. Our results suggest a potential correlation between the low gene flow in I. ovatus populations and the spatially heterogeneous Rickettsia infection rates observed along the altitudinal gradient. This information can be used in understanding the relationship between the tick vector, its pathogen, and environmental factors, such as altitude, and for the control of tick-borne diseases in Japan.


Assuntos
Ixodes , Ixodidae , Infecções por Rickettsia , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Animais , Ixodes/genética , Altitude , Filogenia , Ixodidae/microbiologia , Infecções por Rickettsia/microbiologia , Rickettsia/genética , Estruturas Genéticas
20.
Parasitol Int ; 101: 102891, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38537686

RESUMO

Malaria remains a significant global public health concern, with a recent increase in the number of zoonotic malaria cases in Southeast Asian countries. However, limited reports on the vector for zoonotic malaria exist owing to difficulties in detecting parasite DNA in Anopheles mosquito vectors. Herein, we demonstrate for the first time that several Anopheles mosquitoes contain simian malaria parasite DNA using droplet digital PCR (ddPCR), a highly sensitive PCR method. An entomological survey was conducted to identify simian malaria vector species at Phra Phothisat Temple (PPT), central Thailand, recognized for a high prevalence of simian malaria in wild cynomolgus macaques. A total of 152 mosquitoes from six anopheline species were collected and first analyzed by a standard 18S rRNA nested-PCR analysis for malaria parasite which yielded negative results in all collected mosquitoes. Later, ddPCR was used and could detect simian malaria parasite DNA, i.e. Plasmodium cynomolgi, in 25 collected mosquitoes. And this is the first report of simian malaria parasite DNA detection in Anopheles sawadwongporni. This finding proves that ddPCR is a powerful tool for detecting simian malarial parasite DNA in Anopheles mosquitoes and can expand our understanding of the zoonotic potential of malaria transmission between monkeys and humans.


Assuntos
Anopheles , Malária , Mosquitos Vetores , Reação em Cadeia da Polimerase , Anopheles/parasitologia , Animais , Reação em Cadeia da Polimerase/métodos , Malária/transmissão , Malária/epidemiologia , Malária/parasitologia , Malária/diagnóstico , Mosquitos Vetores/parasitologia , Tailândia/epidemiologia , RNA Ribossômico 18S/análise , RNA Ribossômico 18S/genética , Plasmodium/isolamento & purificação , Plasmodium/genética , Macaca fascicularis/parasitologia , DNA de Protozoário/análise , Humanos , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA