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Background: Ivermectin, an effective treatment for scabies, is not licensed for children weighing <15 kg. Pharmacokinetic modelling has shown a 3 mg dose in young children (2-4 years, weighing 10-14 kg) achieves comparable drug exposure to a 200 µg/kg dose in children aged ≥5 years. This trial evaluated a 3 mg dose in young children. Methods: Multicentre, phase 2 trial in five health centres in Lao PDR. Children aged 2-4 years, weighing 10-14 kg with scabies received 3 mg ivermectin and had two plasma concentrations determined (Clinicaltrials.gov ID NCT05500326). On day 14, clinical outcomes and adverse effects were assessed, and a second dose given to complete treatment. The primary outcome was the mean plasma ivermectin exposure (AUC0-∞) after the first dose (compared to a historical control of Indigenous Australian children aged ≥5 years weighing ≥15 kg receiving 200 µg/kg). Secondary outcomes were clinical improvement and adverse effects. Findings: Overall, 100 children with a median age of 3.0 years (IQR 2.6-3.9) and weight of 11.9 kg (IQR 11.0-13.1) were enrolled. The mean observed ivermectin AUC0-∞ was comparable to the historical control group aged 5-11 years (815 µg h/L vs 953 µg h/L, p = 0.256). Complete resolution of scabies occurred in 90/99 children by day 14. Adverse effects were mild, occurring in 7/99. Interpretation: A 3 mg ivermectin dose in children aged 2-4 years and weighing 10-14 kg achieved a mean plasma AUC0-∞ comparable to older children, was highly effective in treating scabies and well tolerated. This study supports extending ivermectin treatment to younger children improving global efforts to control this neglected disease. Funding: Project funding provided by a Thrasher Foundation Early Career Research Award.
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Changes to ivermectin (IVM [22,23-dihydro avermectin B1a + 22,23-dihydro avermectin B1b]) toxicokinetics (TK) with and without P-glycoprotein (P-gp) inhibition by cyclosporin A (CsA) were examined in rainbow trout (Oncorhynchus mykiss). Rainbow trout were injected with 175 µg/kg 3H-IVM (8.6 µCi/mg IVM) with or without co-administration of 480 µg/kg CsA into the caudal vasculature. Fish were sacrificed at various time points (0.25, 0.5, 1, 3, 24, 48, 96, and 168 h) for organ and tissue sampling (blood, liver, kidney, gill, intestines, brain [5 regions], eye, gonad, and fat) which were analyzed for IVM-derived radioactivity. The IVM concentration decreased over time in blood, liver, kidney, and gill, while concentrations in other tissues remained constant. The highest maximum IVM concentration (Cmax) was found in kidney, followed by liver; the lowest Cmax was found in eye, followed by brain and adipose tissue. The highest % of the administered dose was found in the blood 15 min post-IVM administration, followed by the intestine at 60 min post-IVM administration. P-gp inhibition by CsA did not significantly affect calculated TK parameters (AUC [7.33 ± 0.73 - 11.5 ± 2.5 mgâ¢h/kg], mean residence time [84.7 ± 21 - 125 ± 55 h], T1/2 [58.7 ± 15 - 86.8 ± 38 h], clearance rate [0.0152 ± 0.0033 - 0.0239 ± 0.0024 L/kgâ¢h], or volume of distribution [1.91 ± 0.47 - 2.02 ± 0.33 L/kg]), but resulted in small but significant changes in the % administered dose found in blood and medulla. These results suggest that P-gp plays a limited role in overall IVM TK, and that its role in xenobiotic protection may be much less robust in fish than it is in mammals.
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Objectives: The aim of this study was to identify factors associated with coverage in community-directed treatment with ivermectin for onchocerciasis control in savannah and forest areas in the Central African Republic. Methods: A cross-sectional study was conducted in 2 districts where onchocerciasis is endemic. We employed a pretested and validated questionnaire that included questions about the sociodemographic characteristics of the respondents and variables relevant to coverage assessment. Multivariate logistic regression analyses were performed to identify the associations between surveyed mass drug administration (MDA) coverage and the variables considered, while accounting for potential confounding factors. A p-value <0.05 was considered statistically significant. Results: At the district level, the MDA program achieved a reach of 87.29% (95% CI, 86.03%-88.55%) in Bossangoa and 61.74% (95% CI, 59.56%-63.92%) in Kémo, compared to the reported rates of 90.02% and 91.70%, respectively. Women in both Bossangoa and Kémo were 1.28 times more likely to have taken ivermectin than men (95% CI, 1.12-1.47, p=0.008; 1.09-2.00, p=0.041, respectively). The age groups of 5-14, 15-24, and 25-34 were statistically associated with better distribution coverage in both districts. Individuals with knowledge of onchocerciasis were more likely to receive ivermectin compared to those without knowledge, with adjusted odds ratios of 1.41 (95% CI, 1.11-2.01, p=0.030) and 3.19 (95% CI, 2.91-4.08, p=0.001), respectively. Conclusions: The authors recommend implementing measures to improve MDA coverage in future campaigns. These measures should include allocating sufficient time for MDA activities, providing health education, and mobilising the entire population.
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Cutaneous larva migrans (CLM), caused by third-stage filariform larvae of cat and dog hookworms, presents as pruritic, serpiginous tracks upon skin penetration by larvae from contaminated soil. Herein, we report the successful treatment of two CLM patients using albendazole and ivermectin combination therapy. A 42-year-old man from Kordofan and a 38-year-old man from White Nile State presented with characteristic lesions on their lower extremities, resolving completely within one week post-treatment without recurrence. This report highlights the potential of combined albendazole-ivermectin therapy in managing CLM amid emerging antihelminthic resistance, suggesting that its broader application warrants further investigation.
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Exploring therapeutic options is crucial in the ongoing COVID-19 pandemic caused by SARS-CoV-2. Nirmatrelvir, which is a potent inhibitor that targets the SARS-CoV-2 Mpro, shows promise as an antiviral treatment. Additionally, Ivermectin, which is a broad-spectrum antiparasitic drug, has demonstrated effectiveness against the virus in laboratory settings. However, its clinical implications are still debated. Using computational methods, such as molecular docking and 100 ns molecular dynamics simulations, we investigated how Nirmatrelvir and Ivermectin interacted with SARS-CoV-2 Mpro(A). Calculations using density functional theory were instrumental in elucidating the behavior of isolated molecules, primarily by analyzing the frontier molecular orbitals. Our analysis revealed distinct binding patterns: Nirmatrelvir formed strong interactions with amino acids, like MET49, MET165, HIS41, HIS163, HIS164, PHE140, CYS145, GLU166, and ASN142, showing stable binding, with a root-mean-square deviation (RMSD) of around 2.0 Å. On the other hand, Ivermectin interacted with THR237, THR239, LEU271, LEU272, and LEU287, displaying an RMSD of 1.87 Å, indicating enduring interactions. Both ligands stabilized Mpro(A), with Ivermectin showing stability and persistent interactions despite forming fewer hydrogen bonds. These findings offer detailed insights into how Nirmatrelvir and Ivermectin bind to the SARS-CoV-2 main protease, providing valuable information for potential therapeutic strategies against COVID-19.
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Antivirais , Tratamento Farmacológico da COVID-19 , Proteases 3C de Coronavírus , Ivermectina , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , SARS-CoV-2 , Ivermectina/química , Ivermectina/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Proteases 3C de Coronavírus/química , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Humanos , Antivirais/química , Antivirais/farmacologia , Ligação Proteica , Sulfonamidas/química , Sulfonamidas/farmacologia , Sítios de Ligação , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Lactamas , Leucina , Nitrilas , ProlinaRESUMO
BACKGROUND: Evidence on ivermectin as a treatment for Covid-19 is controversial. A Cochrane review concluded that the efficacy and safety of ivermectin is uncertain (evidence up to April 2022) and WHO recommended its use only in the setting of clinical trials. This study aimed to assess the efficacy and safety of oral ivermectin in hospitalized patients with mild to moderate Covid-19. TRIAL DESIGN AND METHODS: A double-blind, randomized placebo-controlled clinical trial was conducted among RT-PCR-confirmed, adults, hospitalised within the first four days of symptoms. Patients received oral ivermectin 24 mg or placebo daily for five days. RT-PCR was repeated on days five and ten. Clinical progression was monitored using the World Health Organization Clinical Progression Scale. Serum ivermectin levels were measured on days three, five, and seven. The primary outcome was the difference in the viral load between day zero and ten in the two groups. RESULTS: Out of 1699 patients screened, 249 underwent randomization and 127 received ivermectin, and 122 placebo. D10 median viral load for E gene (IQR) was 2,000 copies/mL (100 - 20,500) with ivermectin (n = 80) and 4,100 copies/mL (1,000-65,600) with placebo (n = 81, p = 0.028), per protocol analysis. The difference in Log viral load between day zero and ten between ivermectin and placebo was 3.72 and 2.97 respectively (p = 0.022). There was no significant difference in the WHO clinical progression scale or the adverse effects. Ivermectin blood levels taken before or with meals were not significantly different. Only 7 and 17 patients achieved blood levels above 160ng/ML and 100ng/ML respectively and they did not achieve a significantly lower viral load. CONCLUSION: Although ivermectin resulted in statistically significant lower viral load in patients with mild to moderate Covid-19, it had no significant effect on clinical symptoms. TRIAL REGISTRATION NUMBER: SLCTR/2021/020, Sri Lanka Clinical Trials Registry. 19/07/2021.
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Tratamento Farmacológico da COVID-19 , Ivermectina , SARS-CoV-2 , Carga Viral , Humanos , Ivermectina/administração & dosagem , Ivermectina/efeitos adversos , Ivermectina/uso terapêutico , Método Duplo-Cego , Masculino , Feminino , Pessoa de Meia-Idade , Administração Oral , Carga Viral/efeitos dos fármacos , Adulto , SARS-CoV-2/genética , SARS-CoV-2/efeitos dos fármacos , Resultado do Tratamento , COVID-19/virologia , Idoso , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Antivirais/efeitos adversosRESUMO
The current study assessed the efficacy of Acyclovir (ACV) and Ivermectin (IVM) as monotherapies and combined treatments for intestinal and muscular stages of Trichinella spiralis infection. One-hundred Swiss albino mice received orally 250 ± 50 infectious larvae and were divided into infected-untreated (Group-1), IVM-treated (Group-2), ACV-treated (Group-3), combined IVM+ACV (Group-4), and healthy controls (Group-5). Each group was subdivided into subgroup-A-enteric phase (10 mice, sacrificed day-7 p.i.) and subgroup-B-muscular phase (10 mice, sacrificed day-35 p.i.). Survival rate and body weight were recorded. Parasite burden and intestinal histopathology were assessed. In addition, immunohistochemical expression of epithelial CDX2 in the intestinal phase and CyclinD1 as well as CD34 in the muscular phase were evaluated. Compared, IVM and ACV monotherapies showed insignificant differences in the amelioration of enteric histopathology, except for lymphocytic counts. In the muscle phase, monotherapies showed variable disruptions in the encapsulated larvae. Compared with monotherapies, the combined treatment performed relatively better improvement of intestinal inflammation and reduction in the enteric and muscular parasite burden. CDX2 and CyclinD1 positively correlated with intestinal inflammation and parasite burden, while CD34 showed a negative correlation. CDX2 positively correlated with CyclinD1. CD34 negatively correlated with CDX2 and CyclinD1. IVM +ACV significantly ameliorated CDX2, CyclinD1, and CD34 expressions compared with monotherapies. Conclusion. T. spiralis infection-associated inflammation induced CDX2 and CyclinD1 expressions, whereas CD34 was reduced. The molecular tumorigenic effect of the nematode remains questionable. Nevertheless, IVM +ACV appeared to be a promising anthelminthic anti-inflammatory combination that, in parallel, rectified CDX2, CyclinD1, and CD34 expressions.
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Evidence shows that tropomodulin 1 (TMOD1) is a powerful diagnostic marker in the progression of several cancer types. However, the regulatory mechanism of TMOD1 in tumor progression is still unclear. Here, we showed that TMOD1 was highly expressed in acute myeloid leukemia (AML) specimens, and TMOD1-silencing inhibited cell proliferation by inducing autophagy in AML THP-1 and MOLM-13 cells. Mechanistically, the C-terminal region of TMOD1 directly bound to KPNA2, and TMOD1-overexpression promoted KPNA2 ubiquitylation and reduced KPNA2 levels. In contrast, TMOD1-silencing increased KPNA2 levels and facilitated the nuclear transfer of KPNA2, then subsequently induced autophagy and inhibited cell proliferation by increasing the nucleocytoplasmic transport of p53 and AMPK activation. KPNA2/p53 inhibitors attenuated autophagy induced by silencing TMOD1 in AML cells. Silencing TMOD1 also inhibited tumor growth by elevating KPNA2-mediated autophagy in nude mice bearing MOLM-13 xenografts. Collectively, our data demonstrated that TMOD1 could be a novel therapeutic target for AML treatment.
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The mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase 5 (ERK5) is emerging as a promising target in cancer. Indeed, alterations of the MEK5/ERK5 pathway are present in many types of cancer, including melanoma. One of the key events in MAPK signalling is MAPK nuclear translocation and its subsequent regulation of gene expression. Likewise, the effects of ERK5 in supporting cancer cell proliferation have been linked to its nuclear localization. Despite many processes regulating ERK5 nuclear translocation having been determined, the nuclear transporters involved have not yet been identified. Here, we investigated the role of importin subunit alpha (α importin) and importin subunit beta-1 (importin ß1) in ERK5 nuclear shuttling to identify additional targets for cancer treatment. Either importin ß1 knockdown or the α/ß1 importin inhibitor ivermectin reduced the nuclear amount of overexpressed and endogenous ERK5 in HEK293T and A375 melanoma cells, respectively. These results were confirmed in single-molecule microscopy in HeLa cells. Moreover, immunofluorescence analysis showed that ivermectin impairs epidermal growth factor (EGF)-induced ERK5 nuclear shuttling in HeLa cells. Both co-immunoprecipitation experiments and proximity ligation assay provided evidence that ERK5 and importin ß1 interact and that this interaction is further induced by EGF administration and prevented by ivermectin treatment. The combination of ivermectin and the ERK5 inhibitor AX15836 synergistically reduced cell viability and colony formation ability in A375 and HeLa cells and was more effective than single treatments in preventing the growth of A375 and HeLa spheroids. The increased reduction of cell viability upon the same combination was also observed in patient-derived metastatic melanoma cells. The combination of ivermectin and ERK5 inhibitors other than AX15836 provided similar effects on cell viability. The identification of importin ß1 as the nuclear transporter of ERK5 may be exploited for additional ERK5-inhibiting strategies for cancer therapy.
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The present study aimed to analyze the cladistics and population structure analysis of Rhipicephalus microplus ticks infesting buffaloes in Haryana, India, as well as the assessment of the anti-tick efficacy of the ethanolic extracts of Cassia fistula (bark, pod pulp, and flowers) against R. microplus larvae. The molecular characterization and population structure analysis were performed by targeting the amplification of the partial mitochondrial cytochrome C oxidase subunit 1 (cox1) gene, whereas anti-tick efficacy was evaluated using a larval packet test. The sequences generated herein revealed a homology of 98.26-100% to the GenBank-archived R. microplus sequences. In population structure analysis, high haplotype (0.500 ± 0.265) and low nucleotide (0.002 ± 0.001) diversities were recorded for the sequences generated in this study. Significantly negative neutrality indices were recorded for the overall dataset. The extracts were found to significantly affect mortality rates in a dose-dependent manner, and the ethanolic extracts of the bark, pod pulp, and flowers of C. fistula exhibited median lethal concentration (LC50) values of 27.989, 40.457, and 49.43 mg/mL, respectively. The LC50 value recorded for the combination of the ethanolic extracts of the bark, flower, and pod pulp of C. fistula was 19.724 mg/mL, whereas the synthetic acaricide ivermectin had an LC50 value of 351.56 mg/mL. In conclusion, R. microplus populations infesting cattle and buffalo hosts in India exhibited negligible genetic differentiation and high gene flow between them. Additionally, the combination of all C. fistula extracts could serve as a potential substitute for the synthetic acaricide.
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PURPOSE: Global fears regarding future epidemics of new and re-emerging infections will prompt clinicians to try out unconventional treatments based on limited evidence, including the repurposing of existing drugs. The dilemma involves balancing clinical intuition with the need to rely on low-quality information because of the scarcity of definitive evidence. An example was ivermectin; with its potential antiviral properties, it was promoted for its efficacy in treating coronavirus disease 2019 despite conflicting outcomes in clinical trials and varying expert opinions. This article describes the development of a decision-making framework to resolve such dilemmas. METHODS: The case study from Sri Lanka illustrates multiple challenges faced by clinicians. As the horrific details of deaths in countries such as Italy spread on social media, there was panic and an unprecedented demand for clinicians and health services to provide effective treatment. This led to the popularity of drugs such as ivermectin and several herbal cures. However, there was no consensus among experts on the efficacy of ivermectin, which eventually led to the authorities to recommend limited approval for use under physician supervision. FINDINGS: The situation lent itself to a framework with 4 elements: prerequisites, applying an appropriate decision-making tool (eg, multiple criteria decision-making methods), ethical considerations, and sensitive communication. IMPLICATIONS: We propose this framework for clinicians when they face similar situations with demands to repurpose medicines with inconclusive evidence of efficacy to combat devastating infections from new or re-emerging infections.
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The population of South American camelids (SAC) has been steadily growing in Europe, where they are confronted with the regional endoparasite population of ruminants. As there are no anthelmintic drugs registered for use against nematode infections in SACs, anthelmintics (AH) available for ruminants or horses are usually applied. Reports indicating potential failures in administered AH are increasing. However, the generally low egg counts in SACs complicate the application of resistance tests in the field. The present study reports a follow-up study on SAC farms where anthelmintic resistance (AR) was suspected. The aims were (i) to repeat faecal egg count reduction tests (FECRTs) on potentially affected farms identified in a previous study with larger sample sizes, (ii) to verify suspected AR of Haemonchus contortus against benzimidazoles (BZ) by performing a single-nucleotide polymorphism (SNP) analysis using digital polymerase chain reaction (dPCR), and (iii) to apply the mini-FLOTAC technique for more reliable results at low egg counts in line with current recommendations. Seven farms (9-46 animals each) were examined by coproscopy, larval differentiation and SNP analysis. A FECRT was performed on six of these farms with moxidectin (three farms), monepantel (two farms) and ivermectin (one farm). The FEC was calculated according to the current World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines with the clinical protocol (a newly introduced variant of FECRT which can be used for smaller sample sizes and lower egg counts on the cost of sensitivity) and an expected efficacy of 99%. A high level (> 90%) of BZ-resistance-associated SNPs on codon 200 of H. contortus was observed on all farms. With the FECRT, resistance was demonstrated for ivermectin (74% FECR), while it remained inconclusive for one farm for moxidectin treatment. Sustained efficacy was demonstrated for the remaining treatments. This study showed an advanced level of BZ resistance in H. contortus of SACs and the development of AR against macrocyclic lactones on some farms. Thus, constant monitoring of AH treatment and sustainable worm control methods both need to be applied.
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Anti-Helmínticos , Benzimidazóis , Camelídeos Americanos , Resistência a Medicamentos , Fezes , Hemoncose , Haemonchus , Contagem de Ovos de Parasitas , Animais , Haemonchus/efeitos dos fármacos , Haemonchus/genética , Resistência a Medicamentos/genética , Anti-Helmínticos/farmacologia , Hemoncose/veterinária , Hemoncose/parasitologia , Hemoncose/tratamento farmacológico , Contagem de Ovos de Parasitas/veterinária , Benzimidazóis/farmacologia , Fezes/parasitologia , Camelídeos Americanos/parasitologia , Alelos , Polimorfismo de Nucleotídeo Único , Lactonas/farmacologia , Alemanha , Macrolídeos/farmacologiaRESUMO
Ivermectin, a broad-spectrum anti-parasitic drug, has been proposed as a novel vector control tool to reduce malaria transmission by mass drug administration. Ivermectin and some metabolites have mosquito-lethal effect, reducing Anopheles mosquito survival. Ivermectin inhibits liver stage development in a rodent malaria model, but no inhibition was observed in a primate malaria model or in a human malaria challenge trial. In the liver, cytochrome P450 3A4 and 3A5 enzymes metabolize ivermectin, which may impact drug efficacy. Thus, understanding ivermectin metabolism and assessing this impact on Plasmodium liver stage development is critical. Using primary human hepatocytes (PHHs), we characterized ivermectin metabolism and evaluated the efficacy of ivermectin and its primary metabolites M1 (3â³-O-demethyl ivermectin) and M3 (4-hydroxymethyl ivermectin) against Plasmodium falciparum liver stages. Two different modes of ivermectin exposure were evaluated: prophylactic mode (days 0-3 post-infection) and curative mode (days 3-5 post-infection). We used two different PHH donors and modes to determine the inhibitory concentration (IC50) of ivermectin, M1, M3, and the known anti-malarial drug pyrimethamine, with IC50 values ranging from 1.391 to 14.44, 9.95-23.71, 4.767-8.384, and 0.9073-5.416 µM, respectively. In our PHH model, ivermectin and metabolites M1 and M3 demonstrated inhibitory activity against P. falciparum liver stages in curative treatment mode (days 3-5) and marginal activity in prophylactic treatment mode (days 0-3). Ivermectin had improved efficacy when co-administered with ketoconazole, a specific inhibitor of cytochrome P450 3A4 enzyme. Further studies should be performed to examine ivermectin liver stage efficacy when co-administered with CYP3A4 inhibitors and anti-malarial drugs to understand the pharmacokinetic and pharmacodynamic drug-drug interactions that enhance efficacy against human malaria parasites in vitro.
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Hepatócitos , Ivermectina , Plasmodium falciparum , Ivermectina/farmacologia , Hepatócitos/parasitologia , Hepatócitos/efeitos dos fármacos , Humanos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/crescimento & desenvolvimento , Citocromo P-450 CYP3A/metabolismo , Antimaláricos/farmacologia , Fígado/parasitologia , Fígado/efeitos dos fármacos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Animais , Células Cultivadas , Anopheles/parasitologia , Anopheles/efeitos dos fármacosRESUMO
Ivermectin (IVM) is a broad-spectrum veterinary antiparasitic used worldwide in cattle breeding. The aim of this study was to evaluate the lethal effects of the active ingredient and a commercial formulation of IVM (1 % active ingredient) in the embryonic stage (S. 4-6) and larval stage (S. 25) of the South American amphibian Rhinella arenarum through chronic standardized bioassays. Also, behavior analysis and oxidative stress and cholinergic effects biomarkers were analyzed at 1, 10 and 100 µg IVM/L concentrations. For the embryonic stage, the active ingredient (96 h- LC50: 15900 µg/L) was more toxic than the commercial formulation (96 h-LC50: 51230 µg/L) during the acute period, while at chronic exposure the commercial formulation was more toxic (504 h-LC50: 10.25 µg/L), compared to the active ingredient (504 h-LC50: 312.80 µg/L). For the larval stage, in acute exposure, the active ingredient (96 h-LC50: 800 µg/L) was more toxic than the commercial formulation (96 h-LC50: 1550 µg/L). In the chronic exposure, the commercial formulation (504 h-LC50: 77.33 µg/L) was more toxic than the active ingredient (504 h-LC50: 195.25 µg/L). Overall, larvae exhibited greater sensitivity to both the active ingredient and the commercial formulation. However, during chronic exposure, embryos were more sensitive to the commercial formulation than larvae. The commercial formulation primarily induced oxidative stress, and both forms of the compound affected behavior and cholinergic effect biomarkers, even at low environmentally relevant concentrations (1 µg/L). These results highlight the potential impact of IVM on aquatic ecosystems.
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Ivermectina , Larva , Estresse Oxidativo , Poluentes Químicos da Água , Animais , Ivermectina/toxicidade , Poluentes Químicos da Água/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Larva/efeitos dos fármacos , Antiparasitários/toxicidade , Bufonidae , Dose Letal Mediana , Ecotoxicologia , Embrião não Mamífero/efeitos dos fármacosRESUMO
Macropinocytosis is a cellular process that enables cells to engulf extracellular material, such as nutrients, growth factors, and even whole cells. It is involved in several physiological functions as well as pathological conditions. In cancer cells, macropinocytosis plays a crucial role in promoting tumor growth and survival under nutrient-limited conditions. In particular KRAS mutations have been identified as main drivers of macropinocytosis in pancreatic, breast, and non-small cell lung cancers. We performed a high-content screening to identify inhibitors of macropinocytosis in pancreatic ductal adenocarcinoma (PDAC)-derived cells, aiming to prevent nutrient scavenging of PDAC tumors. The screening campaign was conducted in a well-known pancreatic KRAS-mutated cell line (MIAPaCa-2) cultured under nutrient deprivation and using FITC-dextran to precisely quantify macropinocytosis. We assembled a collection of 3584 small molecules, including drugs approved by the Food and Drug Administration (FDA), drug-like molecules against molecular targets, kinase-targeted compounds, and molecules designed to hamper protein-protein interactions. We identified 28 molecules that inhibited macropinocytosis, with potency ranging from 0.4 to 29.9 µM (EC50). A few of them interfered with other endocytic pathways, while 11 compounds did not and were therefore considered specific "bona fide" macropinocytosis inhibitors and further characterized. Four compounds (Ivermectin, Tyrphostin A9, LY2090314, and Pyrvinium Pamoate) selectively hampered nutrient scavenging in KRAS-mutated cancer cells. Their ability to impair albumin-dependent proliferation was replicated both in different 2D cell culture systems and 3D organotypic models. These findings provide a new set of compounds specifically targeting macropinocytosis, which could have therapeutic applications in cancer and infectious diseases.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Pinocitose , Pinocitose/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , MutaçãoRESUMO
INTRODUCTION: We systematically assessed benefits and harms of the use of ivermectin in non-hospitalized patients with early COVID-19. METHODS: Five databases were searched until October 17, 2023, for randomized controlled trials (RCTs) in adult patients with COVID-19 treated with ivermectin against standard of care (SoC), placebo, or active drug. Primary outcomes were hospitalization, all-cause mortality, and adverse events (AEs). Secondary outcomes included mechanical ventilation (MV), clinical improvement, clinical worsening, viral clearance, and severe adverse events (SAEs). Random effects meta-analyses were performed, with quality of evidence (QoE) evaluated using GRADE methods. Pre-specified subgroup analyses (ivermectin dose, control type, risk of bias, follow-up, and country income) and trial sequential analysis (TSA) were performed. RESULTS: Twelve RCTs (n = 7,035) were included. The controls were placebo in nine RCTs, SoC in two RCTs, and placebo or active drug in one RCT. Ivermectin did not reduce hospitalization (relative risk [RR], 0.81, 95% confidence interval [95% CI] 0.64-1.03; 8 RCTs, low QoE), all-cause mortality (RR 0.98, 95% CI 0.73-1.33; 9 RCTs, low QoE), or AEs (RR 0.89, 95% CI 0.75-1.07; 9 RCTs, very low QoE) vs. controls. Ivermectin did not reduce MV, clinical worsening, or SAEs and did not increase clinical improvement and viral clearance vs. controls (very low QoE for secondary outcomes). Subgroup analyses were mostly consistent with main analyses, and TSA-adjusted risk for hospitalization was similar to main analysis. CONCLUSIONS: In non-hospitalized COVID-19 patients, ivermectin did not have effect on clinical, non-clinical or safety outcomes versus controls. Ivermectin should not be recommended as treatment in non-hospitalized COVID-19 patients.
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Tratamento Farmacológico da COVID-19 , Ivermectina , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Ivermectina/uso terapêutico , Ivermectina/efeitos adversos , Humanos , SARS-CoV-2/efeitos dos fármacos , Hospitalização/estatística & dados numéricos , Resultado do Tratamento , COVID-19/mortalidade , Antivirais/uso terapêutico , Antivirais/efeitos adversos , Respiração Artificial/estatística & dados numéricosRESUMO
BACKGROUND: Preventive chemotherapy with ivermectin and albendazole (IA) in mass drug administration (MDA) programs for all at-risk populations is the core public health intervention to eliminate lymphatic filariasis (LF). Achieving this goal depends on drug effectiveness in reducing parasite reservoirs in the community to halt transmission. We assessed the efficacy of ivermectin and albendazole in clearing microfilariae and circulating filarial antigens (CFA) following MDA. METHODS: This community-based prospective study was conducted in Mkinga district, Tanga region, Tanzania, from November 2018 to June 2019. A total of 4115 MDA-eligible individuals were screened for CFA using Filarial test strips. CFA positives were re-examined for microfilariae by microscopy. CFA and microfilariae positive individuals were enrolled and received IA through MDA campaign. The status of microfilariae and CFA was monitored before MDA, and on day 7 and six-month following MDA. The primary efficacy outcomes were the clearance rates of microfilariae on day 7 and six-months, and CFA at 6 months of post-MDA. The McNemar test assessed the proportions of microfilariae positive pre- and post-MDA, while Chi-square tests were utilized to examine factors associated with CFA status six months post-MDA. RESULTS: Out of 4115 individuals screened, 239 (5.8%) tested positive for CFA, of whom 11 (4.6%) were also positive for microfilariae. Out of the ten microfilariae-positive individuals available for follow-up on day 7, nine tested negative, yielding a microfilariae clearance rate of 90% [95% confidence interval (CI): 59.6-98.2%]. Participants who tested negative for microfilariae on day 7 remained free of microfilariae six months after MDA. However, those who did not clear microfilariae on day-7 remained positive six-months post-MDA. The McNemar test revealed a significant improvement in microfilariae clearance on day 7 following MDA (P = 0.02). Out of 183 CFA-positive individuals who were available at 6-month follow-up, 160 (87.4%) remained CFA positive, while 23 became CFA negative. The CFA clearance rate at 6 months post-MDA was 12.6% (95% CI: 8.5-8.5%). There was no significant association of variability in ivermectin plasma exposure, measured by maximum concentration or area under the curve, and the clearance status of microfilariae or CFA post-MDA. CONCLUSIONS: Preventive chemotherapy with IA effectively clears microfilariae within a week. However, it is less effective in clearing CFA at six months of post-MDA. The low clearance rate for filarial antigenemia underscores the need for alternative drug combinations and additional preventive measures to achieve LF elimination by 2030.
Assuntos
Albendazol , Filariose Linfática , Filaricidas , Ivermectina , Administração Massiva de Medicamentos , Ivermectina/uso terapêutico , Ivermectina/administração & dosagem , Albendazol/uso terapêutico , Albendazol/administração & dosagem , Tanzânia/epidemiologia , Humanos , Filariose Linfática/prevenção & controle , Filariose Linfática/tratamento farmacológico , Filariose Linfática/transmissão , Estudos Prospectivos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Animais , Criança , Filaricidas/uso terapêutico , Filaricidas/administração & dosagem , Quimioterapia Combinada , Microfilárias/efeitos dos fármacos , Idoso , Pré-Escolar , Antígenos de Helmintos/sangue , Resultado do TratamentoRESUMO
The variability in the expression of different P-glycoprotein (P-gp) genes in parasitic nematodes of ruminants such as Haemonchus contortus (Hco-pgp) may be caused by different factors including nematode biology, geographical region and anthelmintic pressure. This study analysed the relative expression level of 10 P-gp genes in two H. contortus (Hco-pgp) field isolates from Yucatan, Mexico: 1) PARAISO (IVM-resistant) and 2) FMVZ-UADY (IVM-susceptible). These isolates were compared with a susceptible reference isolate from Puebla, Mexico, namely "CENID-SAI". In all cases H. contortus adult males were used. The Hco-pgp genes (1, 2, 3, 4, 9, 10, 11, 12, 14 and 16) were analysed for each isolate using the RT-qPCR technique. The Hco-pgp expressions were pairwise compared using the 2-ΔΔCt method and a t-test. The PARAISO isolate showed upregulation compared to the CENID-SAI isolate for Hco-pgp 1, 3, 9, 10 and 16 (P < 0.05), and the PARAISO isolate showed upregulation vs. FMVZ-UADY isolate for Hco-pgp 2 and 9 (P < 0.05), displaying 6.58- and 5.93-fold differences (P < 0.05), respectively. In contrast, similar Hco-pgp gene expression levels were recorded for FMVZ-UADY and CENID-SAI isolates except for Hco-pgp1 (P <0.1), which presented a significant upregulation (6.08-fold). The relative expression of Hco-pgp allowed confirming the IVM-resistant status of the PARAISO isolate and the IVM-susceptible status of the FMVZ-UADY isolate when compared to the CENID-SAI reference isolate. Therefore, understanding the association between the Hco-pgp genes expression of H. contortus and its IVM resistance status could help identifying the genes that could be used as molecular markers in the diagnosis of IVM resistance. However, it is important to consider the geographic origin of the nematode isolate and the deworming history at the farm of origin.