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1.
Sci Rep ; 15(1): 1756, 2025 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-39800782

RESUMO

Recently, it has been shown that sugar­conditioned honey bees can be biased towards a nectarless dioecious crop as kiwifruit. The challenges for an efficient pollination service in this crop species are its nectarless flowers and its short blooming period. It is known that combined non-sugar compounds (NSCs) present in the floral products of different plants, such as caffeine and arginine, enhance olfactory memory retention in honey bees. Additionally, these NSCs presented in combination with scented food improve pollination activity in nectar crops. Here, we evaluated the effect of kiwifruit mimic-scented sugar solution (KM) on colonies located in this crop by supplementing them either with these NSCs individually (KM + CAF, KM + ARG), or combined (KM + MIX). Our results show an increase in colonies' activity after feeding for all treatments. However, the colonies supplemented with the combined mixture (KM + MIX) collected heavier kiwifruit pollen loads and showed an increasing pollen stored area in their hives compared to the KM-treated control colonies. Unexpectedly, the caffeine-treated colonies showed a decrease in the pollen foraging related responses. These results show a combined effect of NSCs that improves honey bee pollen foraging in a nectarless crop, however this activity is impaired when caffeine is used alone for a nectarless crop.


Assuntos
Néctar de Plantas , Pólen , Polinização , Abelhas/fisiologia , Abelhas/efeitos dos fármacos , Animais , Néctar de Plantas/química , Pólen/química , Polinização/efeitos dos fármacos , Flores , Açúcares , Actinidia/química , Cafeína/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Produtos Agrícolas
2.
Biochim Biophys Acta Biomembr ; : 184405, 2024 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-39706462

RESUMO

In this work, the effects of L- Arginine (L-Arg) insertion on saturated and unsaturated lipid membranes were assessed by fluorescence spectroscopy, dynamic light scattering (DLS) and monolayer measurements. The studied systems were composed by DPPC, 16:0 DietherPC, 16:1 Δ9-CisPC, DPPC:Chol, 16:1 Δ9-CisPC:Chol, and 16:1 Δ9-CisPC:DPPC in the presence of increasing concentrations of L-Arg. The information obtained using fluorescence spectral Laurdan properties indicates that L- Arg produces a decrease in the polarizability of saturated lipids congruent with the increase in vesicle size and area per lipid. However, in unsaturated lipids, the polarizability increases without significant changes in size and area per lipid denoting a different mechanism of insertion. The two opposite effects can be modulated by the saturated and unsaturated ratio and are independent of carbonyl groups. This modulation is damped by cholesterol. The differences in the L-Arg insertion can be explained considering that in the presence of the double bond, L-Arg decreases the organized water in the lipid matrix without expanding the bilayer. Instead, in saturated lipid membranes, L-Arg inserts into the acyl chains dragging water and expanding the membrane area.

3.
Nutrients ; 16(23)2024 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-39683461

RESUMO

BACKGROUND AND AIMS: Post-exercise recovery strategies include massage, low-intensity active exercise, thermal contrast, hydration, and nutritional and herbal approaches. These strategies aim to accelerate recovery, enhance performance, and optimise the physical training process. L-arginine (L-ARG) is the physiological precursor of nitric oxide (NO), a crucial mediator of vasodilation and the inhibition of platelet aggregation. A previous study reported that L-ARG supplementation could significantly reduce the systolic blood pressure (SBP) and diastolic blood pressure (DBP). This study aimed to investigate the effects of L-ARG on autonomic and cardiovascular recovery immediately following submaximal exercise. METHODS AND RESULTS: Thirty-two healthy individuals were subjected to two experimental protocols. The first protocol included 60 min of rest, a treadmill warm-up, and load increments until reaching 80% of their maximum HR. Before this protocol, the subjects consumed 3 g of starch (placebo protocol). The second protocol was identical, but the subjects consumed 3 g of L-ARG. Heart rate recovery (HRR), heart rate variability (HRV), and blood pressure (BP) responses were assessed. No significant differences in HRR were found (p = 0.944) regarding the root mean square of successive differences in the RR interval (RMSSD30) of HRV (p = 0.562) or in the BP responses (mean arterial pressure (MAP), p = 0.687; pulse pressure (PP), p = 0.929) between the protocols. CONCLUSIONS: L-ARG supplementation did not significantly alter immediate post-exercise autonomic recovery in healthy males.


Assuntos
Arginina , Sistema Nervoso Autônomo , Pressão Sanguínea , Estudos Cross-Over , Suplementos Nutricionais , Exercício Físico , Frequência Cardíaca , Humanos , Masculino , Frequência Cardíaca/efeitos dos fármacos , Arginina/administração & dosagem , Exercício Físico/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Adulto , Adulto Jovem , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiologia , Voluntários Saudáveis
4.
Future Microbiol ; : 1-12, 2024 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-39508342

RESUMO

Aim: To study the influence of varying concentrations of arginine (Arg) combined with fluoride (F) and/or calcium glycerophosphate (CaGP) on biofilms.Materials & methods: Biofilms were analyzed for acidogenicity, microbial viability and Ca, F and inorganic phosphorus (P) concentrations.Results: For total bacteria, the lowest viability was found in F-containing groups, regardless of the arginine concentrations and presence of CaGP. For aciduric bacteria, no significant differences were found among arginine concentrations in the presence of F. For MS, arginine concentrations did not influence MS viability in the presence of fluoride and CaGP only decreased viability at 3.2% Arg concentration. The arginine-treated groups showed the lowest acidogenicity. For ion concentrations in biofilms, CaGP showed the highest values for P; Arg+F for F; and CaGP/Arg+CaGP for Ca.Conclusion: Different concentrations of arginine did not affect the microbial viability or acidogenicity of biofilms. Moreover, 0.8% Arg did not increase ion concentration in biofilm fluid.


[Box: see text].

5.
Environ Epidemiol ; 8(6): e356, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39600525

RESUMO

Background: Ambient fine particulate matter (PM2.5) is a risk factor for atherosclerosis disease. We aimed to assess whether nitric oxide stable metabolites (NOx) and l-arginine mediate the association between PM2.5 and carotid intima media thickness (cIMT) increase. Methods: We selected 251 participants from the control group of GEA (Genetics of Atheroslerosis Disease Mexican) study (2008-2013) in Mexico City. Mediation models were carried out using pathway analyses, a special case of structural equation models. Results: The median concentration of PM2.5 area under the curve (auc) was 25.2 µg/m3 (interquartile range: 24.2-26.4 µg/m3). Employing participants with observed values for both biomarkers (n = 117), the total effect of PM2.5auc on mean cIMT at bilateral, right, and left was 19.27 µm (95% confidence interval [CI]: 5.77, 32.78; P value = 0.005), 12.69 µm (95% CI: 0.67, 24.71; P value = 0.039), and 25.86 µm (95% CI: 3.18, 48.53; P value = 0.025) per each 1 µg/m3 increase of PM2.5auc. The direct effect of PM2.5auc (per 1 µg/m3 increase) was 18.89 µm (95% CI: 5.37, 32.41; P value = 0.006) for bilateral, 13.65 µm (95% CI: 0.76, 26.55; P value = 0.038) for right, and 24.13 µm (95% CI: 3.22, 45.03; P value = 0.024) for left. The indirect effects of NOx and l-arginine were not statistically significant showing that endothelial function biomarkers did not mediate PM2.5 and cIMT associations. Although l-arginine was not a mediator in the PM2.5 and cIMT pathway, a decrease in l-arginine was significantly associated with PM2.5auc. Conclusions: In this study of adults from Mexico City, we found that PM2.5 was associated with an increase in cIMT at bilateral, left, and right, and these associations were not mediated by endothelial function biomarkers (l-arginine and NOx).

6.
Rev Argent Microbiol ; 56(4): 364-367, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39358169

RESUMO

The brown dog tick (Rhipicephalus sanguineus) is the vector of Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever (RMSF) in Northern Mexico and Southwestern United States. The immune response to a tick protein in the sera of humans or animals may reveal the zones with a high propensity to acquire RMSF, and vector control strategies may be focused on these zones. Arginine kinase (AK) is a highly antigenic invertebrate protein that may serve as a marker for tick exposure. We used R. sanguineus recombinant AK in an indirect ELISA assay with RMSF-positive patient sera. The response to AK was significantly higher against the sera of RMSF patients than the control sera from healthy participants without contact with dogs. To validate the antigenicity of tick AK, we mutated one predicted conformational epitope to alanine residues, which reduced the recognition by RMSF patients' immunoglobulins. This preliminary result opens a perspective towards the development of a complimentary technique based on RsAK as an antigen biomarker for vector serological surveillance for Rickettsia RMSF prevention.


Assuntos
Arginina Quinase , Biomarcadores , Rhipicephalus sanguineus , Rickettsia rickettsii , Febre Maculosa das Montanhas Rochosas , Animais , Febre Maculosa das Montanhas Rochosas/epidemiologia , Rhipicephalus sanguineus/microbiologia , Arginina Quinase/imunologia , Arginina Quinase/genética , Biomarcadores/sangue , Humanos , Rickettsia rickettsii/imunologia , Rickettsia rickettsii/genética , Ensaio de Imunoadsorção Enzimática , Cães , Anticorpos Antibacterianos/sangue , Vetores Aracnídeos/microbiologia
7.
Biochem Biophys Rep ; 40: 101837, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39435382

RESUMO

The enzyme arginine kinase (AK), EC 2.7.3.3, catalyzes the reversible phosphorylation of arginine with adenosine triphosphate, forming phosphoarginine, which acts as an energy reservoir due to its high-energy phosphate content that can be rapidly transferred to ADP for ATP renewal. It has been proposed that AK should be associated with some ATP biosynthesis mechanisms, such as glycolysis and oxidative phosphorylation. Arginine kinase is an analogue of creatine kinase found in vertebrates. A literature survey has recovered the physicochemical and structural characteristics of AK. This enzyme is widely distributed in invertebrates such as protozoa, bacteria, porifera, cnidaria, mollusca, and arthropods. Arginine kinase may be involved in the response to abiotic and biotic stresses, being up regulated in several organisms and controlling energy homeostasis during environmental changes. Additionally, phosphoarginine plays a role in providing energy for the transport of protozoa, the beating of cilia, and flagellar movement, processes that demand continuous energy. Arginine kinase is also associated with allergies to shellfish and arthropods, such as shrimp, oysters, and cockroaches. Phenolic compounds such as resveratrol, which decrease AK activity by 50 % in Trypanosoma cruzi, inhibit the growth of the epimastigote and trypomastigote forms, making them a significant target for the development of medications for Chagas Disease treatment.

8.
Pathogens ; 13(10)2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39452749

RESUMO

L-arginine metabolism through arginases and inducible nitric oxide synthase (NOS2) constitutes a fundamental axis for the resolution or progression of Chagas disease. Infection with Trypanosoma cruzi can cause a wide spectrum of disease, ranging from acute forms contained by the host immune response to chronic ones, such as the chronic chagasic cardiomyopathy. Here, we analyzed, in an in vitro model, the ability of two T. cruzi isolates, with different degrees of virulence, to regulate the metabolism of L-arginine through arginase 1 (Arg-1) and NOS2 in macrophages and through arginase 2 (Arg-2) and NOS2 in cardiomyocytes. Stimulation of bone marrow-derived macrophages (BMMΦ), obtained from CD1 mice, with TNF-α + IFN-γ induced their polarization into classically activated macrophages (CAMΦ), which expressed functional NOS2, while stimulation with IL-4 induced their polarization into alternatively activated macrophages (AAMΦ), which expressed functional Arg-1. Interestingly, stimulation of cardiomyocytes, obtained from hearts of CD1 neonatal mice, with TNF-α + IFN-γ or IL-4 also resulted in functional NOS2 and arginase expression, as observed in CAMΦ and AAMΦ, but Arg-2 was the arginase isoform expressed instead of Arg-1. We observed that infection of BMMΦ with the more virulent T. cruzi isolate (QRO) importantly diminished NOS2 expression and nitric oxide (NO) production in CAMΦ, allowing parasite survival, while infection with the less virulent isolate (CI2) did not diminish NOS2 activity and NO production in CAMΦ to a great extent, which resulted in parasite killing. Regarding Arg-1, infection of BMMΦ with the QRO isolate significantly induced Arg-1 expression and activity in AAMΦ, which resulted in a higher parasite load than the one in the unstimulated BMMΦ. Even though infection with CI2 isolate did not increase Arg-1 expression and activity in AAMΦ, the parasite load was higher than the one in the unstimulated BMMΦ but at a lesser magnitude than that observed during infection with the QRO isolate. On the other hand, infection of cardiomyocytes with either QRO or CI2 isolates and further stimulation with TNF-α + IFN-γ inhibited NOS2 expression and NO production, leading to amelioration of infection. Surprisingly, infection of cardiomyocytes with either QRO or CI2 isolates and further stimulation with IL-4 strongly inhibited Arg-2 expression and function, which resulted in parasite loads similar to those observed in unstimulated cardiomyocytes. Our results suggest that T. cruzi isolates that exhibit variable virulence or pathogenicity degrees differentially regulate L-arginine metabolism through Arg-1/2 and NOS2 in macrophages and cardiomyocytes.

9.
Chem Biol Interact ; 403: 111216, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39218371

RESUMO

Leishmaniasis is a neglected tropical disease caused by parasites of the genus Leishmania and is responsible for more than 1 million new cases and 70,000 deaths annually worldwide. Treatment has high costs, toxicity, complex and long administration time, several adverse effects, and drug-resistant strains, therefore new therapies are urgently needed. Synthetic compounds have been highlighted in the medicinal chemistry field as a strong option for drug development against different diseases. Organic salts (OS) have multiple biological activities, including activity against protozoa such as Leishmania spp. This study aimed to investigate the in vitro leishmanicidal activity and death mechanisms of a thiohydantoin salt derived from l-arginine (ThS) against Leishmania amazonensis. We observed that ThS treatment inhibited promastigote proliferation, increased ROS production, phosphatidylserine exposure and plasma membrane permeabilization, loss of mitochondrial membrane potential, lipid body accumulation, autophagic vacuole formation, cell cycle alteration, and morphological and ultrastructural changes, showing parasites death. Additionally, ThS presents low cytotoxicity in murine macrophages (J774A.1), human monocytes (THP-1), and sheep erythrocytes. ThS in vitro cell treatment reduced the percentage of infected macrophages and the number of amastigotes per macrophage by increasing ROS production and reducing TNF-α levels. These results highlight the potential of ThS among thiohydantoins, mainly related to the arginine portion, as a leishmanicidal drug for future drug strategies for leishmaniasis treatment. Notably, in silico investigation of key targets from L. amazonensis, revealed that a ThS compound from the l-arginine amino acid strongly interacts with arginase (ARG) and TNF-α converting enzyme (TACE), suggesting its potential as a Leishmania inhibitor.


Assuntos
Arginina , Leishmania , Macrófagos , Simulação de Acoplamento Molecular , Espécies Reativas de Oxigênio , Animais , Arginina/farmacologia , Arginina/química , Arginina/metabolismo , Camundongos , Humanos , Leishmania/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/parasitologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ovinos , Antiprotozoários/farmacologia , Antiprotozoários/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Eritrócitos/metabolismo , Linhagem Celular , Leishmania mexicana/efeitos dos fármacos , Leishmania mexicana/metabolismo , Células THP-1 , Fator de Necrose Tumoral alfa/metabolismo
10.
JCEM Case Rep ; 2(9): luae099, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39156001

RESUMO

Neurocytomas are neuronal tumors that are usually intraventricular. Rare cases can arise from extraventricular sites. To our knowledge, only 29 cases of extraventricular neurocytoma of the sellar region (EVNSR) have been reported in the literature. We describe a case of a 39-year-old woman who presented with a one-month history of refractory headache, nausea and vomiting. Magnetic resonance imaging (MRI) showed a 5.1 × 3.1 × 2.2 cm sellar and suprasellar mass, suggestive of a pituitary adenoma (PA). She had hyponatremia, obstructive hydrocephalus, and panhypopituitarism at presentation (hypogonadism, adrenal insufficiency). After glucocorticoid replacement therapy and ventriculoperitoneal shunt, the vomiting and headache resolved, but she remained with nausea and hyponatremia. She was submitted to surgery, and histopathological analysis revealed a neurocytoma with positive immunostaining for arginine vasopressin. Syndrome of inappropriate antidiuresis (SIAD) was diagnosed but did not resolve after surgery due to residual tumor, despite fluid restriction and saline replacement. SIAD later resolved with empagliflozin. In conclusion, EVNSR is extremely rare and can be misdiagnosed as PA on MRI. In the context of SIAD and extraventricular neurocytoma, a secreting arginine vasopressin tumor must be considered. SIAD can be challenging to treat, with excision of the EVNSR the treatment choice and, alternatively, empagliflozin associated with fluid restriction.

11.
Heliyon ; 10(13): e34036, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39071691

RESUMO

Loxosceles spp. spiders can cause serious public health issues. Chemical control is commonly used, leading to health and environmental problems. Identifying molecular targets and using them with natural compounds can help develop safer and eco-friendlier biopesticides. We studied the kinetics and predicted structural characteristics of arginine kinase (EC 2.7.3.3) from Loxosceles laeta (LlAK), a key enzyme in the energy metabolism of these organisms. Additionally, we explored (-)-epigallocatechin gallate (EGCG), a green tea flavonoid, as a potential lead compound for the LlAK active site through fluorescence and in silico analysis, such as molecular docking and molecular dynamics (MD) simulation and MM/PBSA analyses. The results indicate that LlAK is a highly efficient enzyme (K m Arg 0.14 mM, K m ATP 0.98 mM, k cat 93 s-1, k cat/K m Arg 630 s-1 mM-1, k cat/K m ATP 94 s-1 mM-1), which correlates with its structure similarity to others AKs (such as Litopenaeus vannamei, Polybetes pythagoricus, and Rhipicephalus sanguineus) and might be related to its important function in the spider's energetic metabolism. Furthermore, the MD and MM/PBSA analysis suggests that EGCG interacted with LlAK, specifically at ATP/ADP binding site (RMSD <1 nm) and its interaction is energetically favored for its binding stability (-40 to -15 kcal/mol). Moreover, these results are supported by fluorescence quenching analysis (K d 58.3 µM and K a 1.71 × 104 M-1). In this context, LlAK is a promising target for the chemical control of L. laeta, and EGCG could be used in combination with conventional pesticides to manage the population of Loxosceles species in urban areas.

12.
Animals (Basel) ; 14(13)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38997969

RESUMO

The objective of this exploratory study was to assess if microencapsulated arginine influences the physicochemical quality of beef. The study included three genetic groups: Angus, Hereford, and Angus × Hereford crossbreed. Two encapsulation systems were used with carnauba wax, at ratios of 3:1 and 2:1, carnauba wax:core (arginine), respectively. A control treatment was also included with no arginine addition. Encapsulated arginine with a 3:1 ratio increased redness by 19.66 at 28 d aged beef compared to the control and 2:1 ratio with values of 18.55 and 16.77, respectively (p = 0.01). Encapsulated arginine at a 3:1 ratio showed the lowest meat shear force values with 24.32 N at 28 d of ageing (p < 0.001). The Angus breed also had a low value of 24.02 N (p < 0.001). Finally, the highest values of intramuscular fat were observed with the inclusion of arginine in a 3:1 ratio. The fat value reached 2.12% with a 3:1 ratio (p = 0.002), while in the Angus breed it was 1.59%. The addition of carnauba wax-encapsulated arginine can improve meat quality. It enhances red color, tenderness, and marbling in bovine meat.

13.
Clin Oral Investig ; 28(7): 366, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850383

RESUMO

OBJECTIVES: This study examined the impact of premedication with ibuprofen and ibuprofen-arginine and the influence of preoperative pain and anxiety on inferior alveolar nerve block (IANB) efficacy in cases of symptomatic irreversible pulpitis. MATERIALS AND METHODS: The study involved 150 SIP patients who were randomly assigned to receive ibuprofen (600 mg), ibuprofen-arginine (1,155 mg), or a placebo 30 min before IANB. Preoperative anxiety and pain levels were assessed using the Modified Dental Anxiety Scale and the Heft-Parker visual scale. IANB efficacy was determined by the absence of or mild pain during the procedure. Statistical analysis included chi-square, z-tests, Analysis of Variance, and Student's t tests. RESULTS: The ibuprofen and ibuprofen-arginine groups exhibited significantly higher IANB success rates (62% and 78%, respectively) compared to the placebo group (34%). However, no significant difference was observed between the ibuprofen and ibuprofen-arginine groups. Patients with successful IANB in the ibuprofen and ibuprofen-arginine groups displayed lower median anxiety scores (8) than those with failed blocks (15) and lower mean preoperative pain scores (118.3). CONCLUSION: In cases of symptomatic irreversible pulpitis the preemptive medication with ibuprofen-arginine effectively increased the efficacy of the inferior alveolar nerve block The inferior alveolar nerve block efficacy was influenced by preoperative anxiety levels and the intensity of pain. CLINICAL RELEVANCE: This research underscores the potential benefits of oral premedication with ibuprofen and ibuprofen-arginine in improving anesthesia outcomes in cases of symptomatic irreversible pulpitis.


Assuntos
Arginina , Ibuprofeno , Nervo Mandibular , Bloqueio Nervoso , Medição da Dor , Pulpite , Humanos , Pulpite/cirurgia , Ibuprofeno/uso terapêutico , Ibuprofeno/administração & dosagem , Método Duplo-Cego , Masculino , Bloqueio Nervoso/métodos , Feminino , Arginina/uso terapêutico , Arginina/administração & dosagem , Adulto , Anestesia Dentária/métodos , Resultado do Tratamento , Pessoa de Meia-Idade , Combinação de Medicamentos
14.
J Dent ; 146: 105039, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714243

RESUMO

OBJECTIVE: The aim of this work was to evaluate the antibiofilm and anticaries properties of the association of arginine (Arg) with calcium glycerophosphate (CaGP) and fluoride (F). METHODS: An active attachment, polymicrobial biofilm model obtained from saliva and bovine teeth discs were used. After the initial biofilm growth period, the enamel discs were transferred to culture medium. The treatment solutions were added to the culture media to achieve the desired final concentration. The following groups were used: negative control (Control); F (110 ppm F); CaGP (0.05 %); Arg (0.8 %) and their associations (F + CaGP; Arg + F; Arg + CaGP; Arg +F + CaGP). The following analyses were carried out: bacterial viability (total bacteria, aciduric bacteria and mutans streptococci), pH assessment of the spent culture medium, dry weight quantification, evaluation of surface hardness loss (%SH) and subsurface mineral content. Normality and homoscedasticity were tested (Shapiro-Wilk and Levene's test) and the following tests were applied: two-way ANOVA (acidogenicity), Kruskall-Wallis (microbial viability) and one way ANOVA (dry weight, %SH, mineral content). RESULTS: The association Arg + F + CaGP resulted in the lowest surface hardness loss in tooth enamel (-10.9 ± 2.3 %; p < 0.05). Arg +F + CaGP exhibited highest values of subsurface mineral content (10.1 ± 2.9 gHAP/cm3) in comparison to Control and F (p < 0.05). In comparison to Control and F, Arg +F + CaGP promoted the highest reduction in aciduric bacteria and mutans streptococci (5.7 ± 0.4; 4.4 ± 0.5 logCFU/mL, p < 0.05). CONCLUSIONS: The Arg-F-Ca association demonstrated to be the most effective combination in protecting the loss of surface hardness and subsurface mineral content, in addition to controlling important virulence factors of the cariogenic biofilm. CLINICAL SIGNIFICANCE: Our findings provide evidence that the Arg-F-Ca association showed an additive effect, particularly concerning protection against enamel demineralization. The combination of these compounds may be a strategy for patients at high risk of caries.


Assuntos
Arginina , Biofilmes , Cariostáticos , Cárie Dentária , Esmalte Dentário , Fluoretos , Glicerofosfatos , Viabilidade Microbiana , Saliva , Streptococcus mutans , Arginina/farmacologia , Biofilmes/efeitos dos fármacos , Bovinos , Animais , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Streptococcus mutans/efeitos dos fármacos , Fluoretos/farmacologia , Glicerofosfatos/farmacologia , Cariostáticos/farmacologia , Saliva/microbiologia , Concentração de Íons de Hidrogênio , Cárie Dentária/prevenção & controle , Cárie Dentária/microbiologia , Viabilidade Microbiana/efeitos dos fármacos , Dureza , Humanos , Desmineralização do Dente/prevenção & controle , Desmineralização do Dente/microbiologia , Propriedades de Superfície
15.
Int J Mol Sci ; 25(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38612442

RESUMO

MELAS syndrome, characterized by mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes, represents a devastating mitochondrial disease, with the stroke-like episodes being its primary manifestation. Arginine supplementation has been used and recommended as a treatment for these acute attacks; however, insufficient evidence exists to support this treatment for MELAS. The mechanisms underlying the effect of arginine on MELAS pathophysiology remain unclear, although it is hypothesized that arginine could increase nitric oxide availability and, consequently, enhance blood supply to the brain. A more comprehensive understanding of these mechanisms is necessary to improve treatment strategies, such as dose and regimen adjustments; identify which patients could benefit the most; and establish potential markers for follow-up. This review aims to analyze the existing evidence concerning the mechanisms through which arginine supplementation impacts MELAS pathophysiology and provide the current scenario and perspectives for future investigations.


Assuntos
Acidose Láctica , Síndrome MELAS , Acidente Vascular Cerebral , Humanos , Síndrome MELAS/tratamento farmacológico , Arginina/uso terapêutico , Suplementos Nutricionais
16.
J Dent ; 145: 104997, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38621525

RESUMO

OBJECTIVE: To assess the effects of arginine, with or without sodium fluoride (NaF; 1,450 ppm), on saliva-derived microcosm biofilms and enamel demineralization. METHODS: Saliva-derived biofilms were grown on bovine enamel blocks in 0.2 % sucrose-containing modified McBain medium, according to six experimental groups: control (McBain 0.2 %); 2.5 % arginine; 8 % arginine; NaF; 2.5 % arginine with NaF; and 8 % arginine with NaF. After 5 days of growth, biofilm viability was assessed by colony-forming units counting, laser scanning confocal microscopy was used to determine biofilm vitality and extracellular polysaccharide (EPS) production, while biofilm metabolism was evaluated using the resazurin assay and lactic acid quantification. Demineralization was evaluated by measuring pH in the culture medium and calcium release. Data were analyzed by Kruskal-Wallis' and Dunn's tests (p < 0.05). RESULTS: 8 % arginine with NaF showed the strongest reduction in total streptococci and total microorganism counts, with no significant difference compared to arginine without NaF. Neither 2.5 % arginine alone nor NaF alone significantly reduced microbial counts compared to the control, although in combination, a reduction in all microbial groups was observed. Similar trends were found for biofilm vitality and EPS, and calcium released to the growth medium. CONCLUSIONS: 8 % Arginine, with or without NaF, exhibited the strongest antimicrobial activity and reduced enamel calcium loss. Also, NaF enhanced the effects of 2.5 % arginine, yielding similar results to 8 % arginine for most parameters analyzed. CLINICAL SIGNIFICANCE: The results provided further evidence on how arginine, with or without NaF, affects oral microcosm biofilms and enamel mineral loss.


Assuntos
Arginina , Biofilmes , Cariostáticos , Esmalte Dentário , Microscopia Confocal , Saliva , Fluoreto de Sódio , Desmineralização do Dente , Biofilmes/efeitos dos fármacos , Arginina/farmacologia , Fluoreto de Sódio/farmacologia , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Bovinos , Animais , Desmineralização do Dente/prevenção & controle , Desmineralização do Dente/microbiologia , Cariostáticos/farmacologia , Saliva/microbiologia , Saliva/metabolismo , Saliva/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Cálcio/análise , Cálcio/metabolismo , Streptococcus/efeitos dos fármacos , Xantenos/farmacologia , Contagem de Colônia Microbiana , Oxazinas/farmacologia
17.
Med. infant ; 31(1): 31-36, Marzo 2024. Ilus, Tab
Artigo em Espanhol | LILACS, UNISALUD, BINACIS | ID: biblio-1552833

RESUMO

Introducción: Se ha postulado que el uso de vasopresina tendría efectos beneficiosos en el postoperatorio de cirugía cardiovascular. Objetivo: Evaluar la respuesta a la vasopresina en el postoperatorio (POP) de cirugía de Fontan de nuestra población. Métodos: Estudio de casos y controles anidados en una cohorte retrospectiva. Se incluyeron pacientes con cirugía de Fontan entre 2014 y 2019. Se registraron variables demográficas, datos del cateterismo pre-Fontan, días de asistencia respiratoria mecánica (ARM), necesidad de inotrópicos, diuréticos, diálisis, dieta hipograsa, octreotide, sildenafil y nutrición parenteral total (NPT); balance de fluidos al primer y segundo día POP, necesidad de cateterismo en el POP, días de permanencia de tubo pleural, días de internación, necesidad de reinternación y mortalidad. Se compararon los grupos con y sin vasopresina utilizando la prueba de Mann- Whitney-Wilcoxon test. Se consideró significativa una p < 0.05. Resultados: Del total analizado, 35 pacientes recibieron vasopresina. En el grupo control fueron 58 pacientes con características similares de gravedad sin vasopresina. No se encontraron diferencias en la evolución postoperatoria entre ambos grupos. El grupo con vasopresina recibió en mayor proporción dieta hipograsa. Conclusiones: En nuestra serie el uso de vasopresina no marcó diferencias significativas en términos de morbimortalidad con relación al grupo control (AU)


Introduction: The use of vasopressin has been suggested to have beneficial effects in the postoperative period after cardiovascular surgery. Objective: To evaluate the response to vasopressin in the postoperative period (POP) of Fontan surgery in our population. Methods: Nested case-control study in a retrospective cohort. Patients who underwent Fontan surgery between 2014 and 2019 were included. Demographic variables, pre-Fontan catheterization data, days of mechanical ventilation (MRA), need for inotropics, diuretics, dialysis, low-fat diet, octreotide, sildenafil and total parenteral nutrition (TPN); fluid balance at first and second day POP, need for catheterization at POP, duration of chest tube drainage, days of hospitalization, need for readmission, and mortality were recorded. Groups with and without vasopressin were compared using the Mann-Whitney- Wilcoxon test. A p < 0.05 was considered significant. Results: Of all patients analyzed, 35 received vasopressin. The control group consisted of 58 patients with similar severity characteristics who did not receive vasopressin. No differences were found in the postoperative outcome between the two groups. The vasopressin group received a higher proportion of low-fat diet. Conclusions: In our series the use of vasopressin did not show significant differences in terms of morbidity and mortality compared to the control group (AU)


Assuntos
Humanos , Lactente , Pré-Escolar , Complicações Pós-Operatórias/tratamento farmacológico , Arginina Vasopressina/administração & dosagem , Arginina Vasopressina/uso terapêutico , Técnica de Fontan/efeitos adversos , Antidiuréticos/administração & dosagem , Antidiuréticos/uso terapêutico , Indicadores de Morbimortalidade , Estudos Retrospectivos , Resultado do Tratamento , Hemodinâmica
18.
J Dent ; 142: 104875, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38309571

RESUMO

OBJECTIVE: The application of anti-inflammatories as topical desensitizers before dental bleaching is an approach to reduce bleaching-induced tooth sensitivity (TS). This randomized controlled trial compared the risk and intensity of TS and the color change resulting from in-office dental bleaching after using an experimental desensitizing gel containing ibuprofen and arginine. METHODS: Sixty-two participants with upper canine shades A2 or darker were randomly assigned to either the ibuprofen-arginine desensitizing group or the placebo group. The desensitizing gel was applied for 15 min before in-office bleaching with 35 % hydrogen peroxide gel for 50 min (2 sessions). To assess the absolute risk and intensity of TS, visual (0-10) and numeric rating (0-5) scales were used, and group comparisons were made using the McNemar test, Wilcoxon test, and paired Student t-test (α = 0.05). Color change was evaluated using Vita Classical, Vita Bleachedguide (ΔSGU), and Vita EasyShade (ΔEab, ΔE00, and ΔWID) before and one month after the bleaching procedure. Group comparisons for color change were done using a paired t-test (α = 0.05). RESULTS: The odds ratio for TS was 0.14 [95 % CI 0.02 to 0.6], meaning lower odds of TS for the desensitizing gel. A lower intensity of TS was also observed for the experimental group (p < 0.005) up to 48 h after bleaching. All color evaluation tools demonstrated effective and similar whitening for both groups (p > 0.05). CONCLUSIONS: Using the experimental desensitizing gel containing ibuprofen and arginine effectively reduced the risk and intensity of TS without compromising the bleaching efficacy. CLINICAL RELEVANCE: The topical application of ibuprofen/arginine on the in-office bleaching reduced risk and intensity of bleaching-induced tooth sensitivity.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Humanos , Sensibilidade da Dentina/induzido quimicamente , Sensibilidade da Dentina/prevenção & controle , Clareadores Dentários/efeitos adversos , Ibuprofeno/uso terapêutico , Clareamento Dental/efeitos adversos , Clareamento Dental/métodos , Peróxido de Hidrogênio/efeitos adversos , Compostos de Sódio , Arginina/uso terapêutico , Resultado do Tratamento
19.
Acta Trop ; 261: 107519, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-39746593

RESUMO

Ticks are significant ectoparasites that transmit a variety of pathogens, leading to serious human and animal diseases, including Lyme disease, Rocky Mountain spotted fever, anaplasmosis, and many others. The emergence of acaricide resistance in hard ticks presents a formidable challenge for public health and livestock management, exacerbated by the increasing incidence of tick-borne diseases and associated economic losses, estimated at $20 billion annually in the livestock sector alone. This review examines the mechanisms underlying acaricide resistance, focusing on genetic mutations, metabolic detoxification processes, and behavioral adaptations in tick populations. We detail the role of commercial acaricides in tick control while emphasizing the adverse effects of their overuse, which contributes to the development of resistant strains. Innovative control strategies are explored, including using pesticide synergists that enhance the efficacy of existing acaricides by targeting the tick's phosphagen system. Additionally, this review highlights the importance of understanding the synergistic interactions between various control methods, including non-chemical approaches such as personal protection measures and landscape management. The review concludes by underscoring the urgent need for novel acaricides with new modes of action and implementing regular monitoring practices to combat acaricide resistance effectively. Addressing these challenges is vital for the sustainable management of tick populations and protecting public health and livestock productivity.

20.
Antibiotics (Basel) ; 13(12)2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39766539

RESUMO

Background/Objectives: Cationic surfactants are potential antimicrobial candidates. Even so, they are the foremost irritative and incompatible group, which limits their usage. The incorporation of surfactants in biopolymer-based nanoparticles is a feasible strategy to improve their efficacy and reduce those drawbacks. Methods: Surfactants with one amino acid on the polar head (lauroyl arginine methyl ester-LAM and phenylalanine dodecyl amide-PNHC12) and surfactants with two amino acids on the polar heads, arginine-phenylalanine (Lauroyl phenylalanine arginine methyl esther-C12PAM and phenylalanine-arginine dodecyl amide-PANHC12) were loaded to zein nanoparticles. Their antimicrobial and antibiofilm activities were evaluated. Also, the inhibitory activities of the surfactants and nanoparticles over skin-related enzymes were accessed in silico and in vitro, while their cytotoxicity was determined comparatively over immortal human keratinocytes (HaCaT) and human fibroblasts (3T3). Finally, the Vibrio fisheri luminescence reduction test was used to detect its ecotoxicity. Results: The nanoparticles were obtained successfully and exhibited good biocide activity against a wide range of pathogenic bacteria and yeasts. The surfactants were found active over the enzymes assayed: elastase > tyrosinase > collagenase > lipoxygenase, while the inhibitory activity was superior when nanoencapsulated over the enzymes tyrosinase and lipoxygenase. The surfactants and their corresponding nanoparticles presented acceptable cytotoxic levels, except for PNHC12 in both forms, while their ecotoxicity was limited and acceptable. Conclusions: Accordingly, the nanoencapsulation of the arginine-phenylalanine surfactants loaded to zein nanoparticles was found to be a smart strategy to enhance the antimicrobial activity and improve their selectivity over representative skin and connective tissues cell lines. These biological properties render the arginine-phenylalanine surfactant nanoparticles as promising candidates for antimicrobial and tissue repairing applications in wound treatments.

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