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1.
Antimicrob Agents Chemother ; 68(4): e0120423, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38411047

RESUMO

Primaquine (PQ) is the main drug used to eliminate dormant liver stages and prevent relapses in Plasmodium vivax malaria. It also has an effect on the gametocytes of Plasmodium falciparum; however, it is unclear to what extent PQ affects P. vivax gametocytes. PQ metabolism involves multiple enzymes, including the highly polymorphic CYP2D6 and the cytochrome P450 reductase (CPR). Since genetic variability can impact drug metabolism, we conducted an evaluation of the effect of CYP2D6 and CPR variants on PQ gametocytocidal activity in 100 subjects with P. vivax malaria. To determine gametocyte density, we measured the levels of pvs25 transcripts in samples taken before treatment (D0) and 72 hours after treatment (D3). Generalized estimating equations (GEEs) were used to examine the effects of enzyme variants on gametocyte densities, adjusting for potential confounding factors. Linear regression models were adjusted to explore the predictors of PQ blood levels measured on D3. Individuals with the CPR mutation showed a smaller decrease in gametocyte transcript levels on D3 compared to those without the mutation (P = 0.02, by GEE). Consistent with this, higher PQ blood levels on D3 were associated with a lower reduction in pvs25 transcripts. Based on our findings, the CPR variant plays a role in the persistence of gametocyte density in P. vivax malaria. Conceptually, our work points to pharmacogenetics as a non-negligible factor to define potential host reservoirs with the propensity to contribute to transmission in the first days of CQ-PQ treatment, particularly in settings and seasons of high Anopheles human-biting rates.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária Vivax , Malária , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Malária Vivax/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , NADPH-Ferri-Hemoproteína Redutase , Cloroquina/farmacologia , Citocromo P-450 CYP2D6/genética , Artemisininas/farmacologia , Primaquina/farmacologia , Primaquina/uso terapêutico , Malária/tratamento farmacológico , Plasmodium falciparum , Plasmodium vivax/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-38870082

RESUMO

OBJECTIVES: Primaquine is essential for the radical cure of Plasmodium vivax malaria and must be metabolized into its bioactive metabolites. Accordingly, polymorphisms in primaquine-metabolizing enzymes can impact the treatment efficacy. This pioneering study explores the influence of monoamine oxidase-A (MAO-A) on primaquine metabolism and its impact on malaria relapses. METHODS: Samples from 205 patients with P. vivax malaria were retrospectively analysed by genotyping polymorphisms in MAO-A and cytochrome P450 2D6 (CYP2D6) genes. We measured the primaquine and carboxyprimaquine blood levels in 100 subjects for whom blood samples were available on the third day of treatment. We also examined the relationship between the enzyme variants and P. vivax malaria relapses in a group of subjects with well-documented relapses. RESULTS: The median carboxyprimaquine level was significantly reduced in individuals carrying low-expression MAO-A alleles plus impaired CYP2D6. In addition, this group experienced significantly more P. vivax relapses. The low-expression MAO-A status was not associated with malaria relapses when CYP2D6 had normal activity. This suggests that the putative carboxyprimaquine contribution is irrelevant when the CYP2D6 pathway is fully active. CONCLUSIONS: We found evidence that the low-expression MAO-A variants can potentiate the negative impact of impaired CYP2D6 activity, resulting in lower levels of carboxyprimaquine metabolite and multiple relapses. The findings support the hypothesis that carboxyprimaquine may be further metabolized through CYP-mediated pathways generating bioactive metabolites that act against the parasite.

3.
Sensors (Basel) ; 24(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38474953

RESUMO

The Bio-Radar is herein presented as a non-contact radar system able to capture vital signs remotely without requiring any physical contact with the subject. In this work, the ability to use the proposed system for emotion recognition is verified by comparing its performance on identifying fear, happiness and a neutral condition, with certified measuring equipment. For this purpose, machine learning algorithms were applied to the respiratory and cardiac signals captured simultaneously by the radar and the referenced contact-based system. Following a multiclass identification strategy, one could conclude that both systems present a comparable performance, where the radar might even outperform under specific conditions. Emotion recognition is possible using a radar system, with an accuracy equal to 99.7% and an F1-score of 99.9%. Thus, we demonstrated that it is perfectly possible to use the Bio-Radar system for this purpose, which is able to be operated remotely, avoiding the subject awareness of being monitored and thus providing more authentic reactions.


Assuntos
Radar , Sinais Vitais , Taxa Respiratória , Algoritmos , Emoções , Processamento de Sinais Assistido por Computador
4.
Malar J ; 22(1): 306, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817240

RESUMO

BACKGROUND: Imperfect adherence is a major barrier to effective primaquine radical cure of Plasmodium vivax. This study investigated the effect of reduced adherence on the risk of P. vivax recurrence. METHODS: Efficacy studies of patients with uncomplicated P. vivax malaria, including a treatment arm with daily primaquine, published between January 1999 and March 2020 were identified. Individual patient data from eligible studies were pooled using standardized methodology. Adherence to primaquine was inferred from i) the percentage of supervised doses and ii) the total mg/kg dose received compared to the target total mg/kg dose per protocol. The effect of adherence to primaquine on the incidence of P. vivax recurrence between days 7 and 90 was investigated by Cox regression analysis. RESULTS: Of 82 eligible studies, 32 were available including 6917 patients from 18 countries. For adherence assessed by percentage of supervised primaquine, 2790 patients (40.3%) had poor adherence (≤ 50%) and 4127 (59.7%) had complete adherence. The risk of recurrence by day 90 was 14.0% [95% confidence interval: 12.1-16.1] in patients with poor adherence compared to 5.8% [5.0-6.7] following full adherence; p = 0.014. After controlling for age, sex, baseline parasitaemia, and total primaquine dose per protocol, the rate of the first recurrence was higher following poor adherence compared to patients with full adherence (adjusted hazard ratio (AHR) = 2.3 [1.8-2.9]). When adherence was quantified by total mg/kg dose received among 3706 patients, 347 (9.4%) had poor adherence, 88 (2.4%) had moderate adherence, and 3271 (88.2%) had complete adherence to treatment. The risks of recurrence by day 90 were 8.2% [4.3-15.2] in patients with poor adherence and 4.9% [4.1-5.8] in patients with full adherence; p < 0.001. CONCLUSION: Reduced adherence, including less supervision, increases the risk of vivax recurrence.


Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária Vivax , Humanos , Primaquina/efeitos adversos , Antimaláricos/farmacologia , Plasmodium vivax , Recidiva , Malária Vivax/tratamento farmacológico , Malária Vivax/prevenção & controle , Malária Vivax/complicações , Antagonistas do Ácido Fólico/farmacologia
5.
J Water Health ; 21(10): 1448-1459, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37902201

RESUMO

The establishment of national strategic frameworks for systematic scaling-up of water safety plans (WSPs) implementation needs to overcome major constraints: lack of legislation and policies, and the need for appropriate monitoring tools. In 2018, the Uruguayan regulator for energy and water services promulgated a regulation intended to ensure an ambitious and pragmatic strategy that supports and promotes WSP implementation and auditing at a national scale. The goal is to have all drinking water supply systems with their WSP implemented by 2030. For this, a demanding schedule was recommended considering the size of the drinking water supplies: (i) large systems serving more than 2,000 inhabitants and (ii) small and very small systems serving fewer than 2,000 inhabitants. A mandatory verification through internal and external audits was also established. This work describes the legal and regulatory framework as well as the challenges and opportunities that open up for the generalization of WSP implementation in Uruguay. Despite the impact of COVID-19 on working conditions for water suppliers, as for the year 2022, WSPs have been successfully implemented in 94 water systems serving more than 2.4 million people. Results of successful implementation and auditing processes are presented and discussed covering methods and outcomes.


Assuntos
Água Potável , Qualidade da Água , Humanos , Uruguai , Abastecimento de Água
6.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37628781

RESUMO

Disruptions in the MBD5 gene have been linked with an array of clinical features such as global developmental delay, intellectual disability, autistic-like symptoms, and seizures, through unclear mechanisms. MBD5 haploinsufficiency has been associated with the disruption of primary cilium-related processes during early cortical development, and this has been reported in many neurodevelopmental disorders. In this study, we describe the clinical history of a 12-year-old child harboring a novel MBD5 rare variant and presenting psychomotor delay and seizures. To investigate the impact of MBD5 haploinsufficiency on neural primary cilia, we established a novel patient-derived cell line and used CRISPR-Cas9 technology to create an isogenic control. The patient-derived neural progenitor cells revealed a decrease in the length of primary cilia and in the total number of ciliated cells. This study paves the way to understanding the impact of MBD5 haploinsufficiency in brain development through its potential impact on neural primary cilia.


Assuntos
Epilepsia , Deficiência Intelectual , Transtornos do Neurodesenvolvimento , Criança , Humanos , Deficiência Intelectual/genética , Cílios/genética , Epilepsia/genética , Convulsões , Proteínas de Ligação a DNA/genética
7.
Int J Mol Sci ; 25(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38203335

RESUMO

Results obtained from rat studies indicate that, even at low concentrations, mercurial species cause harmful effects on the kidneys, by inducing the nephrotic oxidative stress response. In the present work, Hg-associated proteins were identified as possible mercury-exposure biomarkers in rat kidneys exposed to low mercury chloride concentrations for 30 days (Hg-30) and 60 days (Hg-60), using metalloproteomic strategies. The renal proteomic profile was fractioned by two-dimensional electrophoresis and the mercury determinations in kidney samples, protein pellets and protein spots were performed using graphite furnace atomic absorption spectrometry. The characterization of Hg-associated protein spots and the analysis of differentially expressed proteins were performed by liquid chromatography, coupled with tandem mass spectrometry. Eleven Hg-associated protein spots with a concentration range of 79 ± 1 to 750 ± 9 mg kg-1 in the Hg-60 group were identified. The characterization and expression analyses allowed the identification of 53 proteins that were expressed only in the Hg-60 group, 13 "upregulated" proteins (p > 0.95) and 47 "downregulated" proteins (p < 0.05). Actin isoforms and hemoglobin subunits were identified in protein spots of the Hg-60 group, with mercury concentrations in the range of 138 to 750 mg kg-1, which qualifies these proteins as potential mercury-exposure biomarkers.


Assuntos
Desequilíbrio Ácido-Base , Mercúrio , Animais , Ratos , Proteínas de Transporte , Cloretos , Proteômica , Cloreto de Mercúrio/toxicidade , Mercúrio/toxicidade , Biomarcadores
8.
Molecules ; 28(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38138643

RESUMO

The aim of the present study was to evaluate the differential expression of plasma proteins in broiler chickens supplemented with different sources (sulfates and hydroxychlorides) and levels of copper (15 and 150 mg kg-1) and manganese (80 and 120 mg kg-1). For this, plasma samples from 40 broiler chickens were used, divided into four experimental groups: S15-80 (15 ppm CuSO4 and 80 ppm MnSO4), S150-120 (150 ppm CuSO4 and 120 ppm MnSO4), H15-80 (15 ppm Cu(OH)Cl and 80 ppm Mn(OH)Cl), and H150-120 (150 ppm Cu(OH)Cl and 120 ppm Mn(OH)Cl). From plasma samples obtained from each bird from the same treatment, four pools were made considering 10 birds per group. Plasma proteome fractionation was performed by 2D-PAGE. Concentrations of the studied minerals were also evaluated in both plasma and protein pellet samples. A higher concentration of Cu and Mn was observed in the plasma and protein pellets of groups that received higher mineral supplementation levels compared to those receiving lower levels. Mn concentrations were higher in plasma and protein pellets of the hydroxychloride-supplemented groups than the sulfate-supplemented groups. Analysis of the gels revealed a total of 40 differentially expressed spots among the four treatments. Supplementation with different sources of minerals, particularly at higher levels, resulted in changes in protein regulation, suggesting a potential imbalance in homeostasis.


Assuntos
Cobre , Manganês , Animais , Manganês/metabolismo , Cobre/metabolismo , Galinhas/metabolismo , Proteômica , Suplementos Nutricionais/análise , Minerais/metabolismo , Sulfatos/metabolismo , Dieta/veterinária , Ração Animal/análise
9.
J Nematol ; 55(1): 20230059, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38264460

RESUMO

Eucalypts are cultivated worldwide, but little is known about their status as hosts of root-knot nematodes (RKN) (Meloidogyne spp.). Moreover, information is scarce regarding the nature of the damage caused by RKN to eucalypt seedlings and trees. To investigate these aspects, we separately inoculated Meloidogyne enterolobii, M. javanica and M. incognita in seedlings of the world's most cultivated eucalypts: Eucalyptus dunni, E. grandis, E. cloeziana, E. camaldulensis, E. saligna, Corymbia citriodora, and the hybrid E. grandis × E. urophylla. After six months of greenhouse cultivation, we assessed nematode reproduction and variables that expressed the seedlings' shoot and root growth. We observed a diverse pattern of host statuses to RKN among the eucalypts, and all three Meloidogyne species reduced (p < 0.05) the root system mass, volume and length of E. grandis, E. saligna and the hybrid E. grandis × E. urophylla. Our results reaffirm previous reports indicating that RKN can delay the growth of seedlings in nurseries, who should thus adopt appropriate sanitary measures to avoid RKN establishment and spread. Moreover, the damage caused by RKN to eucalypts after just six months of cultivation suggests that the growth of eucalypt trees may be affected over the course of several years of cultivation.

10.
BMC Nephrol ; 23(1): 202, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35659594

RESUMO

BACKGROUND: In critically ill patients, acute pain occurs frequently, causes sympathetic activation, release of inflammatory mediators, and potential organ dysfunction, with the kidneys potentially sensitive to inflammation-mediated injury. This study aimed to explore the association between acute pain in critically ill patients and the occurrence of acute kidney injury (AKI). METHODS: Data from a retrospective cohort of adult patients admitted between June 2013 and June 2016 to the Intensive Care Unit (ICU) of a tertiary hospital in São Paulo, Brazil, were analyzed. The main exclusion criteria were ICU length of stay < 48 h, coma, and prior kidney dysfunction. The outcome (AKI) was defined as an elevation in the baseline serum creatinine level of ≥ 0.3 mg/dl and/or > 50% at any time after the first 48 h in the ICU. Multivariable logistic regression and hierarchical cluster analysis were performed. RESULTS: The isolated incidence of pain was 23.6%, and the incidence of pain duration > 5 days was 10.6%. AKI occurred in 31.7% of the cohort. In multivariable logistic analysis, duration of pain > 5 days (OR 5.25 CI 2.19-12.57 p < 0.01) and mechanical ventilation (MV) ≥ 3 days (OR 5.5 CI 2.3-13.5 p < 0.01) were the variables with positive association with AKI. The hierarchical cluster analysis reinforced the relation between AKI, MV and duration of pain. CONCLUSIONS: Pain is an especially important issue in critically ill patients and in this exploratory study it appears to be associated with AKI development. The search for more rigorous pain control in ICU is crucial and can influence organ dysfunction.


Assuntos
Injúria Renal Aguda , Dor Aguda , Injúria Renal Aguda/etiologia , Dor Aguda/complicações , Adulto , Brasil/epidemiologia , Estudos de Coortes , Estado Terminal/epidemiologia , Humanos , Unidades de Terapia Intensiva , Insuficiência de Múltiplos Órgãos , Estudos Retrospectivos , Fatores de Risco
11.
J Nematol ; 54(1): 20220023, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35937922

RESUMO

For decades there have been anecdotal claims of synergistic interactions between plant-parasitic nematodes and soil-borne fungi causing decline of productivity of passion fruit (Passiflora edulis) orchards. An empirical confirmation of these disease complexes would impact disease management and plant breeding for resistance. To test those claims, we subjected passion fruit plants to single or concomitant parasitism by Meloidogyne javanica or M. incognita and Fusarium nirenbergiae or Neocosmospora sp. under controlled conditions. Non-inoculated plants served as control for the assays. The severity of shoot symptoms and variables related to plant growth, the extent of fungal lesions, and nematode reproduction were assessed to characterize the interactions. The shoot symptoms and effect on plant growth induced by the pathogens varied, but no synergy between the pathogens was observed. Moreover, the volume of tissue lesioned by the fungi was not affected by co-parasitism of the nematodes. Conversely, plant resistance to the nematodes was not affected by co-parasitism of the fungi. The interactions M. incognita-F. nirenbergiae, M. incognita-Neocosmospora sp., M. javanica-F. nirenbergiae, and M. javanica-Neocosmospora sp. were not synergistic as previously claimed, but instead neutral.

12.
Environ Monit Assess ; 194(10): 705, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999477

RESUMO

Metalloproteomics is an innovative methodology for identifying of protein-associated mercury. Thus, we analyzed the muscle proteome of Arapaima gigas (pirarucu), collected in the Madeira River of the Brazilian Amazon, to identify protein-associated mercury, with the aim of identifying possible mercury biomarkers in fish muscle tissue. After obtaining the protein pellet, we conducted two-dimensional electrophoresis (2D PAGE) to fractionate the muscle proteome. Total mercury in muscle tissue and protein pellets and mapping of mercury content in protein spots of the 2D PAGE gels was determined using graphite furnace atomic absorption spectrometry (GFAAS). The protein-associated mercury identification was performed using liquid chromatography coupled with sequence mass spectrometry (LC‒MS/MS). Total mercury determinations by GFAAS indicated concentrations on the order of 153 ± 1.90 mg kg-1 and 142 ± 1.50 mg kg-1 (total precipitation of protein fraction) and 139 ± 1.45 mg kg-1 (fractional precipitation of protein fraction) in muscle tissue and protein pellets, respectively. Mercury concentrations in the range of 48 ± 0.90 to 165 ± 3.00 mg kg-1 were found in twelve protein spots. Among the 2D PAGE protein spots, eleven Hg-binding proteins were identified using LC‒MS/MS, which showed characteristics of mercury exposure biomarkers for important metabolic functions, such as five parvalbumin isoforms, triosephosphate isomerase, cofilin 2 (muscle), and fructose-bisphosphate aldolases.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Biomarcadores/metabolismo , Brasil , Cromatografia Líquida , Monitoramento Ambiental , Peixes/metabolismo , Mercúrio/análise , Músculos/química , Proteoma , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
13.
Clin Genet ; 99(4): 588-593, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33439489

RESUMO

Congenital cranial dysinnervation disorders (CCDDs) are a heterogeneous group of neurodevelopmental phenotypes caused by a primary disturbance of innervation due to deficient, absent, or misguided cranial nerves. Although some CCDDs genes are known, several clinical phenotypes and their aetiologies remain to be elucidated. We describe a 12-year-old boy with hypotonia, developmental delay, sensorineural hearing loss, and keratoconjunctivitis due to lack of corneal reflex. He had a long expressionless face, severe oromotor dysfunction, bilateral agenesis/severe hypoplasia of the VIII nerve with marked atresia of the internal auditory canals and cochlear labyrinth malformation. Trio-exome sequencing identified a homozygous loss of function variant in the NEUROG1 gene (NM_006161.2: c.202G > T, p.Glu68*). NEUROG1 is considered a causal candidate for CCDDs based on (i) the previous report of a patient with a homozygous gene deletion and developmental delay, deafness due to absent bilateral VIII nerves, and severe oromotor dysfunction; (ii) a second patient with a homozygous NEUROG1 missense variant and corneal opacity, absent corneal reflex and intellectual disability; and (iii) the knockout mouse model phenotype which highly resembles the disorder observed in humans. Our findings support the growing compelling evidence that loss of NEUROG1 leads to a very distinctive disorder of cranial nerves development.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Nervo Coclear/anormalidades , Proteínas do Tecido Nervoso/genética , Transtornos do Neurodesenvolvimento/genética , Nervo Trigêmeo/anormalidades , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Criança , Deficiências do Desenvolvimento/genética , Nanismo/genética , Perda Auditiva Neurossensorial/genética , Humanos , Deficiência Intelectual/genética , Ceratoconjuntivite/genética , Masculino , Hipotonia Muscular/genética , Proteínas do Tecido Nervoso/fisiologia
14.
Clin Endocrinol (Oxf) ; 95(4): 677-685, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34231242

RESUMO

INTRODUCTION: Heterozygotes (HZs) for 21-hydroxylase deficiency (21OHD) are highly prevalent, ranging from 1:60 to 1:11 for classic and nonclassic (NC) forms, respectively. Detection of HZ and asymptomatic NC by CYP21A2 genotyping is valuable for genetic counselling, but costly, complex and narrowly available. Adrenocorticotropic hormone (ACTH)-stimulated serum 17-hydroxyprogesterone (17P) and 21-deoxycortisol (21DF) discriminate 21OHD phenotypes effectively, notably if measured simultaneously by liquid chromatography-tandem mass spectrometry (LC-MS/MS). OBJECTIVE: This study was performed to reassess former LC-MS/MS-defined post-ACTH 21DF, 17P and cortisol (F) cutoffs in family members at risk for 21OHD. DESIGN AND PATIENTS: Prospective study in which we screened 58 asymptomatic relatives from families with 21OHD patients and compared post-ACTH steroid phenotypes with subsequent genotypes. RESULTS: Post-ACTH 21DF, 17P, F and (21DF + 17P)/F ratio segregate NC, HZ and wild-type (WT) phenotypes (subsequently genotyped) with some overlap. New receiver operating characteristic curve-defined cutoffs for post-ACTH 21DF, 17P and (21DF + 17P)/F ratio are 60 ng/dl, 310 ng/dl and 12 (unitless). Twenty-six of 33 HZ and all 6 NC (82.1%) had post-ACTH 21DF > 60 and 17P > 310 ng/dl, whereas 17/19 WT (89.5%) had values below cutoffs. Post-ACTH 21DF and 17P had a strong positive correlation (r = .9558; p < .001). A (21DF + 17P)/F ratio > 12 correctly identified 36 of 39 HZ plus NC (92.3% sensitivity) with 84.2% specificity (16 of 19 WT). Given the high frequency of 21OHD HZ, the negative prediction of ratio values below 12 excludes heterozygosity in 99.8% and 99.1% for classic and NC mutations, respectively. CONCLUSIONS: Reassessed ACTH-stimulated 21DF and 17P cutoffs by LC-MS/MS (60 and 310 ng/dl, respectively) correctly recognised 82.5% HZ plus NC, but combined precursor-to-product ratio ([21DF + 17P]/F) cutoff of 12 was superior, identifying 92.3% HZ plus NC. Since one WT subject is an outlier (potential HZ), these values would be somewhat better reinforcing their utility for screening asymptomatic relatives at risk for 21OHD.


Assuntos
Hiperplasia Suprarrenal Congênita , Hormônio Adrenocorticotrópico , 17-alfa-Hidroxiprogesterona , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/genética , Cromatografia Líquida , Cortodoxona , Heterozigoto , Humanos , Estudos Prospectivos , Esteroide 21-Hidroxilase/genética , Espectrometria de Massas em Tandem
15.
Clin Chem Lab Med ; 59(6): 1013-1023, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33554525

RESUMO

OBJECTIVES: Results can vary between different free thyroxine (FT4) assays; global standardization would improve comparability of results between laboratories, allowing development of common clinical decision limits in evidence-based guidelines. CONTENT: We summarize the path to standardization of FT4 assays, and challenges associated with FT4 testing in special populations, including the need for collaborative efforts toward establishing population-specific reference intervals. The International Federation of Clinical Chemistry and Laboratory Medicine Committee for Standardization of Thyroid Function Tests has undertaken FT4 immunoassay method comparison and recalibration studies and developed a reference measurement procedure that is currently being validated. Further studies are needed to establish common reference intervals/clinical decision limits. Standardization of FT4 assays will change test results substantially; therefore, a major education program will be required to ensure stakeholders are aware of the benefits of FT4 standardization, planned transition procedure, and potential clinical impact of the changes. Assay recalibration by manufacturers and approval process simplification by regulatory authorities will help minimize the clinical impact of standardization. SUMMARY: Significant progress has been made toward standardization of FT4 testing, but technical and logistical challenges remain. OUTLOOK: Collaborative efforts by manufacturers, laboratories, and clinicians are required to achieve successful global standardization of the FT4 assays.


Assuntos
Prova Pericial , Tiroxina , Humanos , Imunoensaio , Padrões de Referência , Valores de Referência , Testes de Função Tireóidea , Tireotropina
16.
Anal Bioanal Chem ; 413(16): 4161-4180, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34041576

RESUMO

Listeria monocytogenes is an invasive opportunistic foodborne pathogen and its routine surveillance is critical for protecting the food supply and public health. The traditional detection methods are time-consuming and require trained personnel. Lateral flow immunoassay (LFIA), on the other hand, is an easy-to-perform, rapid point-of-care test and has been widely used as an inexpensive surveillance tool. In recent times, nucleic acid-based lateral flow immunoassays (NALFIA) are also developed to improve sensitivity and specificity. A significant improvement in lateral flow-based assays has been reported in recent years, especially the ligands (antibodies, nucleic acids, aptamers, bacteriophage), labeling molecules, and overall assay configurations to improve detection sensitivity, specificity, and automated interpretation of results. In most commercial applications, LFIA has been used with enriched food/environmental samples to ensure detection of live cells thus prolonging the assay time to 24-48 h; however, with the recent improvement in LFIA sensitivity, results can be obtained in less than 8 h with shortened and improved enrichment practices. Incorporation of surface-enhanced Raman spectroscopy and/or immunomagnetic separation could significantly improve LFIA sensitivity for near-real-time point-of-care detection of L. monocytogenes for food safety and public health applications.


Assuntos
Imunoensaio/métodos , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Animais , Anticorpos Imobilizados/química , Microbiologia de Alimentos , Humanos , Imunoensaio/instrumentação , Listeriose/diagnóstico , Ácidos Nucleicos/química , Sistemas Automatizados de Assistência Junto ao Leito
17.
Clin Exp Pharmacol Physiol ; 48(9): 1224-1230, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34080216

RESUMO

Endothelial dysfunction is a hallmark of preeclampsia and the role of nitric oxide (NO) has been extensively studied in this pregnancy complication. In recent years, hydrogen sulphide (H2 S) has arisen as a new gasotransmitter with an impact on endothelial function. However, the involvement of H2 S in the pathophysiology of preeclampsia is not fully understood, and only a few studies with limited sample size have investigated circulating levels of H2 S in preeclamptic patients. Moreover, H2 S levels have not been previously evaluated in gestational hypertension. Furthermore, the relationship between H2 S and NO in these hypertensive disorders of pregnancy has yet to be determined. We measured H2 S levels in plasma of 120 healthy pregnant women, 88 gestational hypertensive and 62 preeclamptic women. We also measured plasma nitrite in a subset of patients and carried out correlation analysis between plasma H2 S and nitrite in these three groups. We found that plasma H2 S was elevated in preeclampsia and further increased in gestational hypertension compared to healthy pregnancy. Plasma nitrite was reduced in gestational hypertension and preeclampsia, and these levels were negatively correlated with H2 S in both gestational hypertension and preeclampsia, but not in healthy pregnancy. Our results indicate that increases in H2 S may represent a mechanism triggered as an attempt to compensate reduced NO in gestational hypertension and preeclampsia. Future studies are warranted to investigate the mechanisms underlying H2 S/NO interaction on mediating endothelial dysfunction in these hypertensive disorders of pregnancy.


Assuntos
Nitritos
18.
J Clin Densitom ; 24(4): 563-570, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34045135

RESUMO

Primary Hyperparathyroidism (PHPT) often leads to bone loss, even in its asymptomatic presentations. Trabecular Bone Score (TBS) is a method to assess the trabecular bone structure of the spine. This study aimed to evaluate TBS measurements combined with Dual X-ray Absorptiometry (DXA) values in the search for more accurate bone fragility risk assessment among PHPT patients. From 2017 to 2019, patients diagnosed with PHPT (n = 64), before surgery, were invited to participate in this study. Bone mineral density (BMD) by DXA at the lumbar spine, total hip, femoral neck, distal third radius, and TBS were determined in patients and controls (n = 63). The vertebral fracture was defined using the Genant method in vertebral images by DXA and vertebral fracture assessment (VFA). Patients and controls did not differ in age, sex, menopausal status, or body mass index (BMI). The PHPT patients presented significantly lower BMD values than the controls in all sites evaluated. The TBS measurements were also statistically lower in PHPT patients than controls (mean TBS PHPT = 1.233 vs TBS controls = 1.280, p = 0.044). Osteoporosis was observed in 50% of PHPT patients and 26.6% of controls (p = 0.02). However, lumbar spine T-Score < -2.5 was observed only in 21.8% of PHPT patients. Vertebral fractures were detected in nine individuals (14%) from the PHPT group and four (6.3%) in the controls (p = 0.24). The TBS area under the curve (AUC) was higher than DXA AUC in all sites, for vertebral fracture assessment. The TBS AUC was significant in the PHPT group (0.75, 95% CI 0.62 - 0.88, p = 0.02) and not significant in the DXA analysis. The ROC curve showed that TBS values < 1.187 are associated with a significantly higher risk of vertebral fracture among PHPT patients (p = 0.02). The TBS used as a complement to DXA measurements is a useful tool which may better assess fragility risk among PHPT patients.


Assuntos
Hiperparatireoidismo Primário , Fraturas por Osteoporose , Absorciometria de Fóton , Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Humanos , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico por imagem
19.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199897

RESUMO

Transthyretin (TTR), a 55 kDa evolutionarily conserved protein, presents altered levels in several conditions, including malnutrition, inflammation, diabetes, and Alzheimer's Disease. It has been shown that TTR is involved in several functions, such as insulin release from pancreatic ß-cells, recovery of blood glucose and glucagon levels of the islets of Langerhans, food intake, and body weight. Here, the role of TTR in hepatic glucose metabolism was explored by studying the levels of glucose in mice with different TTR genetic backgrounds, namely with two copies of the TTR gene, TTR+/+; with only one copy, TTR+/-; and without TTR, TTR-/-. Results showed that TTR haploinsufficiency (TTR+/-) leads to higher glucose in both plasma and in primary hepatocyte culture media and lower expression of the influx glucose transporters, GLUT1, GLUT3, and GLUT4. Further, we showed that TTR haploinsufficiency decreases pyruvate kinase M type (PKM) levels in mice livers, by qRT-PCR, but it does not affect the hepatic production of the studied metabolites, as determined by 1H NMR. Finally, we demonstrated that TTR increases mitochondrial density in HepG2 cells and that TTR insufficiency triggers a higher degree of oxidative phosphorylation in the liver. Altogether, these results indicate that TTR contributes to the homeostasis of glucose by regulating the levels of glucose transporters and PKM enzyme and by protecting against mitochondrial oxidative stress.


Assuntos
Transportador de Glucose Tipo 3/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Fígado/metabolismo , Dinâmica Mitocondrial , Pré-Albumina/fisiologia , Piruvato Quinase/metabolismo , Animais , Feminino , Transportador de Glucose Tipo 3/genética , Transportador de Glucose Tipo 4/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Piruvato Quinase/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-31844010

RESUMO

Mefloquine shows a high capacity to bind plasma proteins, which influences the amount of drug in erythrocytes. The study investigated the association of lipids levels with plasma concentrations of mefloquine and carboxy-mefloquine in 85 Brazilian patients with uncomplicated falciparum malaria. There were no significant associations between the total cholesterol or triglycerides with plasma concentrations of mefloquine and of carboxy-mefloquine. Lipoprotein levels explained 25.68% and 18.31% of mefloquine and carboxy-mefloquine plasma concentrations, respectively.


Assuntos
Antimaláricos/sangue , Artesunato/sangue , Malária Falciparum/tratamento farmacológico , Mefloquina/análogos & derivados , Mefloquina/sangue , Plasmodium falciparum/efeitos dos fármacos , Adulto , Antimaláricos/farmacocinética , Antimaláricos/farmacologia , Artesunato/farmacocinética , Artesunato/farmacologia , Biotransformação , Brasil , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Quimioterapia Combinada , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Humanos , Malária Falciparum/sangue , Malária Falciparum/parasitologia , Masculino , Mefloquina/farmacocinética , Mefloquina/farmacologia , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Índice de Gravidade de Doença , Triglicerídeos/sangue
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