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1.
Eur J Cancer ; 205: 114103, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38729054

RESUMEN

BACKGROUND: PTEN loss and aberrations in PI3K/AKT signaling kinases associate with poorer response to abiraterone acetate (AA) in metastatic castration-resistant prostate cancer (mCRPC). In this study, we assessed antitumor activity of the AKT inhibitor capivasertib combined with enzalutamide in mCRPC with prior progression on AA and docetaxel. METHODS: This double-blind, placebo-controlled, randomized phase 2 trial, recruited men ≥ 18 years with progressing mCRPC and performance status 0-2 from 15 UK centers. Randomized participants (1:1) received enzalutamide (160 mg orally, once daily) with capivasertib (400 mg)/ placebo orally, twice daily on an intermittent (4 days on, 3 days off) schedule. Primary endpoint was composite response rate (RR): RECIST 1.1 objective response, ≥ 50 % PSA decrease from baseline, or circulating tumor cell count conversion (from ≥ 5 at baseline to < 5 cells/7.5 mL). Subgroup analyses by PTENIHC status were pre-planned. RESULTS: Overall, 100 participants were randomized (50:50); 95 were evaluable for primary endpoint (47:48); median follow-up was 43 months. RR were 9/47 (19.1 %) enzalutamide/capivasertib and 9/48 (18.8 %) enzalutamide/placebo (absolute difference 0.4 % 90 %CI -12.8 to 13.6, p = 0.58), with similar results in the PTENIHC loss subgroup. Irrespective of treatment, OS was significantly worse for PTENIHC loss (10.1 months [95 %CI: 4.6-13.9] vs 14.8 months [95 %CI: 10.8-18]; p = 0.02). Most common treatment-emergent grade ≥ 3 adverse events for the combination were diarrhea (13 % vs 2 %) and fatigue (10 % vs 6 %). CONCLUSIONS: Combined capivasertib/enzalutamide was well tolerated but didn't significantly improve outcomes from abiraterone pre-treated mCRPC.

2.
Parasitol Res ; 123(5): 207, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713234

RESUMEN

Biomarkers are specific molecular, histological, or physiological characteristics of normal or pathogenic biological processes and are promising in the diagnosis of gastrointestinal nematodes (GINs). Although some biomarkers have been validated for infection by Ostertagia sp. in cattle raised in temperate regions, there is a lack of information for tropical regions. The aim of this project was to assess potential biomarkers and validate the most promising. In the first study, 36 bovines (Nelore breed) naturally infected by GINs were distributed into two groups: infected (not treated with anthelmintic) and treated (treated with fenbendazole on days 0, 7, 14, 21, 28, 42, and 56). The variables of interest were live weight, fecal egg count, hemogram, serum biochemical markers, phosphorus, gastrin, and pepsinogen. In the second step, pepsinogen was assessed in cattle of the Nelore breed distributed among three groups: infected (not treated with anthelmintic), MOX (treated with moxidectin), and IVM + BZD (treated with ivermectin + albendazole). In the first study, no difference between groups was found for weight, albumin, hematocrit (corpuscular volume [CV]), erythrocytes, or hemoglobin. Negative correlations were found between pepsinogen and both CV and albumin, and albumin was negatively correlated with the percentage of Haemonchus sp. in the fecal culture. Among the biomarkers, only pepsinogen differentiated treated and infected (beginning with the 28th day of the study). In the second study, a reduction in pepsinogen was found after anthelmintic treatment. Therefore, pepsinogen is a promising biomarker of worms in cattle naturally infected by the genera Haemonchus and Cooperia in tropical areas.


Asunto(s)
Biomarcadores , Enfermedades de los Bovinos , Heces , Infecciones por Nematodos , Clima Tropical , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/tratamiento farmacológico , Biomarcadores/sangre , Infecciones por Nematodos/veterinaria , Infecciones por Nematodos/parasitología , Infecciones por Nematodos/tratamiento farmacológico , Heces/parasitología , Recuento de Huevos de Parásitos , Antihelmínticos/uso terapéutico , Nematodos/aislamiento & purificación , Nematodos/clasificación , Nematodos/efectos de los fármacos , Enfermedades Gastrointestinales/parasitología , Enfermedades Gastrointestinales/veterinaria , Parasitosis Intestinales/veterinaria , Parasitosis Intestinales/parasitología , Fenbendazol/uso terapéutico
3.
ACS Chem Biol ; 19(4): 875-885, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38483263

RESUMEN

It is well established that oxaliplatin, one of the three Pt(II) anticancer drugs approved worldwide, and phenanthriplatin, an important preclinical monofunctional Pt(II) anticancer drug, possess a different mode of action from that of cisplatin and carboplatin, namely, the induction of nucleolar stress. The exact mechanisms that lead to Pt-induced nucleolar stress are, however, still poorly understood. As such, studies aimed at better understanding the biological targets of both oxaliplatin and phenanthriplatin are urgently needed to expand our understanding of Pt-induced nucleolar stress and guide the future design of Pt chemotherapeutics. One approach that has seen great success in the past is the use of Pt-click complexes to study the biological targets of Pt drugs. Herein, we report the synthesis and characterization of the first examples of click-capable phenanthriplatin complexes. Furthermore, through monitoring the relocalization of nucleolar proteins, RNA transcription levels, and DNA damage repair biomarker γH2AX, and by investigating their in vitro cytotoxicity, we show that these complexes successfully mimic the cellular responses observed for phenanthriplatin treatment in the same experiments. The click-capable phenanthriplatin derivatives described here expand the existing library of Pt-click complexes. Significantly they are suitable for studying nucleolar stress mechanisms and further elucidating the biological targets of Pt complexes.


Asunto(s)
Antineoplásicos , Nucléolo Celular , Compuestos Organoplatinos , Fenantridinas , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Cisplatino/farmacología , Compuestos Organoplatinos/química , Compuestos Organoplatinos/farmacología , Oxaliplatino/farmacología , Fenantridinas/síntesis química , Fenantridinas/química , Fenantridinas/farmacología , Química Clic , Nucléolo Celular/efectos de los fármacos , Nucléolo Celular/metabolismo
4.
Parasit Vectors ; 17(1): 101, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429835

RESUMEN

BACKGROUND: In Rio Grande do Sul, Brazil, a region with a subtropical climate, Rhipicephalus microplus is present in taurine cattle raised for beef and milk. In addition, ticks resistant to multiple acaricides are present in this region. Recently, fluralaner (isoxazoline) was launched on the market. Thus, there is a need to evaluate the effects of fluralaner for the control of R. microplus on taurine cattle. In addition, occurrence of myiasis by Cochliomyia hominivorax larvae after tick parasitism and weight gain of cattle during the experimental period were evaluated. METHODS: Thirty naturally infested cattle were divided into two experimental groups: T01, treated with fluralaner (2.5 mg/kg) pour-on; T02, control. T01 received fluralaner on Days 0 (early summer in January), 42 and 84 (early autumn), whereas T02, a control group, received palliative treatment with a spray formulation when the group mean was ≥ 30 ticks. Counts of R. microplus females and calculation of the efficacy of fluralaner were performed on Days 3, 7, 14, 28, 35, 42, 56, 70, 84, 98, 112 and 126. The occurrence of myiasis was assessed throughout the study period. In addition, the weight, weight gain and daily weight gain of the animals were evaluated. RESULTS: In the 12 evaluations performed, the parasitic load of T01 was near zero. Fluralaner showed 99.5% efficacy on the 3rd day after the first treatment and 100% efficacy from Day 7 to Day 126. Cochliomyia hominivorax larvae (n = 6; p = 0.0251) were found only in the control group (T02). At the end of the study, the animals subjected to treatments with fluralaner gained 32.8 kg more than the animals in the control group. CONCLUSIONS: Application of fluralaner in summer and autumn, with 42-day intervals between treatments, was effective to control R. microplus on taurine cattle, which also gained more weight than control cattle. Additionally, no cases of myasis were documented in animals treated with fluralaner.


Asunto(s)
Enfermedades de los Bovinos , Isoxazoles , Miasis , Rhipicephalus , Infestaciones por Garrapatas , Femenino , Bovinos , Animales , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/prevención & control , Infestaciones por Garrapatas/veterinaria , Miasis/veterinaria , Larva , Calliphoridae , Aumento de Peso , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/epidemiología
5.
Parasit Vectors ; 17(1): 110, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38449052

RESUMEN

BACKGROUND: The occurrence of higher winter temperatures in Brazilian areas with tropical and highland climates may result in a fifth peak of tick populations during winter in addition to the four generations previously described. Therefore, a strategic control protocol was developed with treatments in two seasons with the objective of controlling the generations of ticks that occur in spring/summer and those that occur in autumn/winter. METHODS: The study was conducted in Mato Grosso do Sul, Brazil, from the beginning of the rainy season, November 2020, to October 2021. In a randomized block design, 36 calves were distributed into three groups: (i) negative control; (ii) traditional strategic control in one season (SC1S), at the beginning of the rainy season; and (iii) strategic control in two seasons (SC2S), at the beginning and end of the rainy season. The SC1S strategic control group was treated on day 0, November 2020, and twice more with intervals of 42 days. The SC2S group received three more treatments beginning on day 182, May 2021, with intervals of 42 days. All treatments consisted of 5% fluralaner (Exzolt® 5%) delivered via a pour-on dose of 1 mL/20 kg body weight. Counts of semi-engorged female ticks were performed on day 3 and every 14 days thereafter, and the animals were weighed at the same time. RESULTS: Fluralaner showed a mean efficacy of more than 95% up to day 294. The two treated groups showed a decrease (P < 0.05) in the average number of ticks on day 3. In the SC2S group, the means were close or equal to zero throughout the study, while in the SC1S group, the means did not differ (P > 0.05) from those of the control group from day 231 onward. The final mean weight gain of each group was 76.40 kg, 98.63 kg, and 115.38 kg for the control, SC1S, and SC2S groups, respectively, differing (P < 0.05) from each other. CONCLUSIONS: Therefore, three applications of fluralaner, with one application every 42 days from the beginning of the rainy season in the middle spring, resulted in effective tick control for 224 days. When three additional treatments were given in autumn/winter with intervals of 42 days between applications, tick counts were reduced throughout the year. This strategic control approach may be indicated in years with climatic conditions that allow that population peaks are expected to occur in the autumn/winter period.


Asunto(s)
Rhipicephalus , Femenino , Bovinos , Animales , Isoxazoles/farmacología , Brasil , Lluvia
6.
Parasit Vectors ; 17(1): 120, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461304

RESUMEN

BACKGROUND: In 2022, fluralaner was launched on the market for use in the control of the cattle tick Rhipicephalus microplus after showing 100% efficacy in registration trials against the causative agents of cattle tick fever (TFAs). The aim of the present study was to determine whether a strategic control regimen against R. microplus using fluralaner (FLU) in Holstein calves grazing in a tropical region would alter the enzootic stability status of cattle tick fever, triggering outbreaks in these animals up to 22 months age. METHODS: In this study, a group of calves treated with FLU was compared with a control group treated with the regimen currently being used on the farm, which consisted of the fipronil + fluazuron formulation (FIFLUA). In the first experiment, the efficacy of the FIFLUA pour-on formulation was evaluated in a field study. In the second experiment, which lasted 550 days, two experimental groups (n = 30/group) of Holstein calves naturally infested with R. microplus were analyzed. Calves aged 4 to 10 months received either a specific treatment regimen with FLU (experimental group) or FIFLUA (control group). During this period, tick counts, animal weight measurement, feces collection (to determine eggs and oocysts per gram of feces), tick fever monitoring, blood smears (to ascertain enzootic stability of the herd), PCR testing for TFAs and serology (indirect enzyme-linked immunosorbent assay [iELISA]) were performed. All calves were evaluated for signs of tick fever between ages 11 and 22 months. RESULTS: FIFLUA showed an acaricidal efficacy of > 90% from post-treatment days 14 to 35. Regarding treatments against the TFAs, the average number of treatments was similar between groups, but animals treated with FLU had a smaller reduction in packed cell volume on some of the evaluation dates of the second and third treatment against TFAs. In calves aged 10 months in the FLU group, B. bovis was not detected by PCR (0/15 samples), 40% of the samples had antibody titers and 33% (10/30) of the samples had positive blood smears. Regarding B. bigemina, > 86% of the samples in both groups tested positive for B. bigemina DNA and antibodies; there was no difference in the antibody titers between the groups. There were no clinical cases of cattle tick fever in calves aged 11 to 22 months. CONCLUSIONS: In comparison with the control treatment, the strategic control regimen against R. microplus with FLU that was implemented in the present study did not negatively affect the enzootic stability status of A. marginale and B. bigemina in the herd up to 22 months of age. The enzootic stability status of B. bovis was not reached by either group. These results likely represent a characteristic of the local tick population, so further studies should be performed.


Asunto(s)
Anaplasmosis , Babesiosis , Enfermedades de los Bovinos , Isoxazoles , Rhipicephalus , Infestaciones por Garrapatas , Animales , Bovinos , Control de Ácaros y Garrapatas , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/prevención & control , Infestaciones por Garrapatas/veterinaria , Enfermedades de los Bovinos/epidemiología , Óvulo , Babesiosis/epidemiología , Anaplasmosis/epidemiología
7.
Biofouling ; 40(2): 165-176, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38425095

RESUMEN

Dual-species biofilms formed by Candida albicans and Staphylococcus aureus have high virulence and drug resistance. In this context, biosurfactants produced by Pseudomonas aeruginosa have been widely studied, of which a new derivative (RLmix_Arg) stands out for possible application in formulations. The objective of this study was to evaluate the antibiofilm activity of RLmix_Arg, both alone and incorporated in a gel prepared with Pluronic F-127, against dual-species biofilms of fluconazole-resistant C. albicans (FRCA) and methicillin-resistant S. aureus (MRSA) in impregnated catheters. Broth microdilution tests, MTT reduction assays of mature biofilms, impregnation of RLmix_Arg and its gel in peripheral venous catheters, durability tests and scanning electron microscopy (SEM) were performed. RLmix_Arg showed antimicrobial activity against Candida spp. and S. aureus, by reducing the cell viability of mixed biofilms of FRCA and MRSA, and preventing their formation in a peripheral venous catheter. The incorporation of this biosurfactant in the Pluronic F-127 gel considerably enhanced its antibiofilm activity. Thus, RLmix_Arg has potential application in gels for impregnation in peripheral venous catheters, helping to prevent development of dual-species biofilms of FRCA and MRSA.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Fluconazol/farmacología , Candida albicans , Staphylococcus aureus , Resistencia a la Meticilina , Biopelículas , Poloxámero/farmacología , Pruebas de Sensibilidad Microbiana , Antiinfecciosos/farmacología , Catéteres , Antibacterianos/farmacología
8.
Mol Cancer Ther ; 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38412481

RESUMEN

Therapies that abrogate persistent androgen receptor (AR) signaling in castration resistant prostate cancer (CRPC) remain an unmet clinical need. The N-terminal domain (NTD) of the AR that drives transcriptional activity in CRPC remains a challenging therapeutic target. Herein we demonstrate that BAG-1 mRNA is highly expressed and associates with signaling pathways, including AR signaling, that are implicated in the development and progression of CRPC. In addition, interrogation of geometric and physiochemical properties of the BAG domain of BAG-1 isoforms identifies it to be a tractable but challenging drug target. Furthermore, through BAG-1 isoform mouse knockout studies we confirm that BAG-1 isoforms regulate hormone physiology and that therapies targeting the BAG domain will be associated with limited 'on-target' toxicity. Importantly, the postulated inhibitor of BAG-1 isoforms, Thio-2, suppressed AR signaling and other important pathways implicated in the development and progression of CRPC to reduce the growth of treatment resistant prostate cancer cell lines and patient derived models. However, the mechanism by which Thio-2 elicits the observed phenotype needs further elucidation since the genomic abrogation of BAG-1 isoforms was unable to recapitulate the Thio-2 mediated phenotype. Overall, these data support the interrogation of related compounds with improved drug-like properties as a novel therapeutic approach in CRPC, and further highlight the clinical potential of treatments that block persistent AR signaling which are currently undergoing clinical evaluation in CRPC.

9.
Chemosphere ; 352: 141444, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38346513

RESUMEN

This study assessed the occurrence of five antibiotics, three hormones, caffeine, and long and short-chain perfluoroalkyl and polyfluoroalkyl substances (PFASs) in surface water and feedstuff samples obtained from aquaculture cages in Três Marias reservoir in Brazil. This is the first work to evaluate the presence of PFAS in surface water used for aquaculture in Brazil. Solid-phase extraction and low temperature partitioning extraction followed by liquid chromatography coupled to mass spectrometry (LC-MS) were performed to process and analyze surface water samples and feedstuff, respectively. The ecotoxicological risk quotient was calculated for target compounds detected in water. Ciprofloxacin and caffeine were detected in all surface water samples. Pharmaceutical drugs ranged from 0.7 ng L-1 (trimethoprim) to 389.2 ng L -1 (ß-estradiol). Estrone (10.24 ng g-1) and ß-estradiol (66.20 ng g-1) were also found in feedstuff. Four PFASs (PFOA, PFDoA, PFTeDA, and PFBS) were detected (9.40-15.2 µg L-1) at levels higher than reported in studies conducted worldwide. Ecotoxicological risk assessment indicated high risks for caffeine and PFOA, PFDoA, and PFTeDA with RQ values from 10 to 103. These findings reveal risks to biodiversity, ecosystem integrity and human health considering possible intake of these contaminants by fish consumption due to potential bioaccumulation of these substances. Hence, it is critical to conduct more studies in this direction in Brazil and other low and middle-low-income countries.


Asunto(s)
Ácidos Alcanesulfónicos , Cíclidos , Fluorocarburos , Contaminantes Químicos del Agua , Humanos , Animales , Agua/análisis , Brasil , Monitoreo del Ambiente , Antibacterianos/análisis , Ácidos Alcanesulfónicos/análisis , Cafeína/análisis , Ecosistema , Estradiol/análisis , Contaminantes Químicos del Agua/análisis , Fluorocarburos/análisis
10.
Acta Biomater ; 178: 93-110, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38382833

RESUMEN

While 3D tumor models have greatly evolved over the past years, there is still a strong requirement for more biosimilar models which are capable of recapitulating cellular crosstalk within the tumor microenvironment while equally displaying representative levels of tumor aggressiveness and invasion. Herein, we disclose an assembloid melanoma model based on the fusion of individual stromal multicellular spheroids (MCSs). In contrast to more traditional tumor models, we show that it is possible to develop self-organizing, heterotypic melanoma models where tumor cells present stem-cell like features like up-regulated pluripotency master regulators SOX2, POU5F1 and NANOG. Additionally, these assembloids display high levels of invasiveness while embedded in 3D matrices as evidenced by stromal cell promotion of melanoma cell invasion via metalloproteinase production. Furthermore, sensitivity to anticancer drug doxorubicin was demonstrated for the melanoma assembloid model. These findings suggest that melanoma assembloids may play a significant role in the field of 3D cancer models as they more closely mimic the tumor microenvironment when compared to more traditional MCSs, opening the doors to a better understanding of the role of tumor microenvironment in supporting tumor progression. STATEMENT OF SIGNIFICANCE: The development of complex 3D tumor models that better recapitulate the tumor microenvironment is crucial for both an improved comprehension of intercellular crosstalk and for more efficient drug screening. We have herein developed a self-organizing heterotypic assembloid-based melanoma model capable of closely mimicking the tumor microenvironment. Key features recapitulated were the preservation of cancer cell stemness, sensitivity to anti-cancer agents and tumor cell invasion promoted by stromal cells. The approach of pre-establishing distinct stromal domains for subsequent combination into more complex tumor constructs provides a route for developing superior tumor models with a higher degree of similarity to native cancer tissues.


Asunto(s)
Melanoma , Humanos , Esferoides Celulares , Microambiente Tumoral , Células del Estroma , Línea Celular Tumoral
11.
Clin Cancer Res ; 30(10): 2140-2159, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38376926

RESUMEN

PURPOSE: The multi-kinase inhibitor (mKi) regorafenib has demonstrated efficacy in chemorefractory patients with metastatic colorectal cancer (mCRC). However, lack of predictive biomarkers and concerns over significant toxicities hamper the use of regorafenib in clinical practice. EXPERIMENTAL DESIGN: Serial liquid biopsies were obtained at baseline and monthly until disease progression in chemorefractory patients with mCRC treated with regorafenib in a phase II clinical trial (PROSPECT-R n = 40; NCT03010722) and in a multicentric validation cohort (n = 241). Tissue biopsies collected at baseline, after 2 months and at progression in the PROSPECT-R trial were used to establish patient-derived organoids (PDO) and for molecular analyses. MicroRNA profiling was performed on baseline bloods using the NanoString nCounter platform and results were validated by digital-droplet PCR and/or ISH in paired liquid and tissue biopsies. PDOs co-cultures and PDO-xenotransplants were generated for functional analyses. RESULTS: Large-scale microRNA expression analysis in longitudinal matched liquid and tissue biopsies from the PROSPECT-R trial identified MIR652-3p as a biomarker of clinical benefit to regorafenib. These findings were confirmed in an independent validation cohort and in a "control" group of 100 patients treated with lonsurf. Using ex vivo co-culture assays paired with single-cell RNA-sequencing of PDO established pre- and post-treatment, we modeled regorafenib response observed in vivo and in patients, and showed that MIR652-3p controls resistance to regorafenib by impairing regorafenib-induced lethal autophagy and by orchestrating the switch from neo-angiogenesis to vessel co-option. CONCLUSIONS: Our results identify MIR652-3p as a potential biomarker and as a driver of cell and non-cell-autonomous mechanisms of resistance to regorafenib.


Asunto(s)
Biomarcadores de Tumor , MicroARN Circulante , Neoplasias Colorrectales , Resistencia a Antineoplásicos , Compuestos de Fenilurea , Piridinas , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/sangre , Compuestos de Fenilurea/farmacología , Compuestos de Fenilurea/uso terapéutico , Piridinas/uso terapéutico , Piridinas/farmacología , Resistencia a Antineoplásicos/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/sangre , Animales , Femenino , Estudios Prospectivos , Masculino , Ratones , Ensayos Antitumor por Modelo de Xenoinjerto , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Anciano , Biopsia Líquida/métodos , Persona de Mediana Edad , Línea Celular Tumoral , MicroARNs/genética , MicroARNs/sangre
12.
J Med Microbiol ; 73(2)2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38385528

RESUMEN

Introduction. Candida albicans and Staphylococcus aureus are recognized for their development of resistance and biofilm formation. New therapeutic alternatives are necessary in this context.Hypothesis. Etomidate shows potential application in catheters against mixed biofilms of fluconazole-resistant C. albicans and methicillin-resistant S. aureus (MRSA).Aim. The present study aimed to evaluate the activity of etomidate against mixed biofilms of fluconazole-resistant C. albicans and MRSA.Methodology. The action of etomidate against mature biofilms was verified through the evaluation of biomass and cell viability, and its ability to prevent biofilm formation in peripheral venous catheters was determined based on counts of colony forming units (c.f.u.) and confirmed by morphological analysis through scanning electron microscopy (SEM).Results. Etomidate generated a reduction (P<0.05) in biomass and cell viability starting from a concentration of 250 µg ml-1. In addition, it showed significant ability to prevent the formation of mixed biofilms in a peripheral venous catheter, as shown by a reduction in c.f.u. SEM revealed that treatment with etomidate caused substantial damage to the fungal cells.Conclusion. The results showed the potential of etomidate against polymicrobial biofilms of fluconazole-resistant C. albicans and MRSA.


Asunto(s)
Etomidato , Staphylococcus aureus Resistente a Meticilina , Fluconazol/farmacología , Candida albicans , Antifúngicos/farmacología , Etomidato/farmacología , Biopelículas , Pruebas de Sensibilidad Microbiana
13.
Future Microbiol ; 19: 91-106, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38294293

RESUMEN

Background: Staphylococcus aureus is a human pathogen responsible for high mortality rates. The development of new antimicrobials is urgent. Materials & methods: The authors evaluated the activity of hydralazine along with its synergism with other drugs and action on biofilms. With regard to action mechanisms, the authors evaluated cell viability, DNA damage and molecular docking. Results: MIC and minimum bactericidal concentration values ranged from 128 to 2048 µg/ml. There was synergism with oxacillin (50%) and vancomycin (25%). Hydralazine reduced the viability of biofilms by 50%. After exposure to hydralazine 2× MIC, 58.78% of the cells were unviable, 62.07% were TUNEL positive and 27.03% presented damage in the comet assay (p < 0.05). Hydralazine showed affinity for DNA gyrase and TyrRS. Conclusion: Hydralazine is a potential antibacterial.


Staphylococcus aureus is a bacterium that can cause infection. Infections of S. aureus are becoming difficult to treat, but developing new drugs is a challenge. Repurposing them may be easier. This study looks at the possibility of using hydralazine, a type of medicine used to treat high blood pressure, against S. aureus. The authors found that hydralazine can kill S. aureus and can be used with other antibiotics, including oxacillin and vancomycin. Hydralazine interferes with important processes for the multiplication and survival of this bacterium. These results are preliminary but encouraging. Further studies are needed to confirm the use of hydralazine as a new treatment for S. aureus infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus , Meticilina , Resistencia a la Meticilina , Simulación del Acoplamiento Molecular , Antibacterianos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Pruebas de Sensibilidad Microbiana
14.
Vet Parasitol Reg Stud Reports ; 47: 100968, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38199704

RESUMEN

The present work evaluated the pharmacokinetics and efficacy of the association of 15cmg/kg toltrazuril +5cmg/kg fenbendazole against Eimeria spp. and gastrointestinal nematodes (GINs) in calves of different regions of Brazil (Center-West, Southeast, and South). A total of seven experiments were carried out, five of which determined formulation efficacy against Eimeria spp., considering the following aspects: therapeutic, preventive, metaphylactic, and residual efficacy. Therapeutic efficacy experiments for GINs were carried out by parasitological necropsy. The toltrazuril + fenbendazole association demonstrated ≥95% efficacy against Eimeria spp. for 21 days post-treatment (DPT). When used preventively and metaphylatically, the same association demonstrated ≥97% efficacy against E. zuernii, E. ellipsoidalis, E. cylindrica, E. bovis, E. wyomingensis and E. auburnensis. Toltrazuril + fenbendazole administered seven days before challenge was 100% effective against all these Eimeria species. Results of therapeutic, preventive, metaphylactic and residual efficacies can be related to the pharmacokinetic results, especially considering toltrazuril sulfone, which was detected in animal plasma for a longer period than the parent compound. Toltrazuril + fenbendazole achieved 100% anthelminthic efficacy against the GINs Haemonchus placei (L4), Cooperia pectinata and Oesophagostomum radiatum; 99.94% against adult H. placei; and 99.98% against C. puntacta. The association of toltrazuril + fenbendazole, associated with other measures, is an important and suitable tool for the control and treatment of Eimeria spp. and GINs in young cattle.


Asunto(s)
Eimeria , Haemonchus , Animales , Bovinos , Fenbendazol/uso terapéutico , Triazinas/uso terapéutico
15.
Parasit Vectors ; 17(1): 15, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38191412

RESUMEN

BACKGROUND: The present study aimed to evaluate the effects of different treatment strategies using a new commercial formulation containing pour-on fluralaner on Rhipicephalus microplus infestation in cattle and in pastures in a tropical climate region where up to five generations of this tick species can occur per year. METHODS: Forty-five naturally infested cattle were divided into three experimental groups: T01, treated with fluralaner (2.5 mg/kg) pour-on every 42 days; T02, the cattle received the first treatment with fluralaner on Day 0 but the next treatment involved a weekly visual evaluation; T03, control, received palliative treatment with a spray formulation when the group mean was ≥ 30 ticks. Counts of female R. microplus were performed weekly until day 343, and larval counts on pasture were performed on Days 0, 30, and 60 and every 30 days until Day 330. RESULTS: Using fluralaner, six applications were performed in Group T01, and four were performed in Group T02. In the control group (T03), it was necessary to perform eight palliative acaricide treatments with the spray formulation. The animals in T01 and T02 showed lower mean tick counts (p ≤ 0.05) than the control group (T03) on 28 and 27 of the 49 evaluated dates, respectively. In the paddock where the animals were kept as controls, the R. microplus larvae counts increased to 1458. In the paddocks where the animals were treated with fluralaner, the number was ≤ 19 per paddock during the study. CONCLUSIONS: The different strategic treatment protocols performed with pour-on fluralaner (2.5 mg/kg) over a year in taurine cattle in a tropical region with a history of up to five annual generations of cattle ticks were effective, maintaining levels of R. microplus infestations in animals and in pastures close to zero in most of the study. Depending on the retreatment criterion adopted, the number of applications per year may be lower, resulting in a reduction in the mean cost of acaricide treatment per year and lower exposure of R. microplus populations to the active ingredient, resulting in lower resistance and selection pressure.


Asunto(s)
Acaricidas , Rhipicephalus , Femenino , Animales , Bovinos , Isoxazoles/uso terapéutico , Larva
16.
J Biomed Sci ; 31(1): 13, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38254117

RESUMEN

Cancer remains a serious burden in society and while the pace in the development of novel and more effective therapeutics is increasing, testing platforms that faithfully mimic the tumor microenvironment are lacking. With a clear shift from animal models to more complex in vitro 3D systems, spheroids emerge as strong options in this regard. Years of development have allowed spheroid-based models to better reproduce the biomechanical cues that are observed in the tumor-associated extracellular matrix (ECM) and cellular interactions that occur in both a cell-cell and cell-ECM manner. Here, we summarize some of the key cellular interactions that drive tumor development, progression and invasion, and how successfully are these interactions recapitulated in 3D spheroid models currently in use in the field. We finish by speculating on future advancements in the field and on how these can shape the relevance of spherical 3D models for tumor modelling.


Asunto(s)
Neoplasias , Animales , Comunicación Celular , Modelos Animales de Enfermedad , Matriz Extracelular , Microambiente Tumoral
17.
Biochem Pharmacol ; 220: 115982, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38097051

RESUMEN

Hyperglycemia is a major risk factor for kidney diseases. Oxidative stress, caused by reactive oxygen species, is a key factor in the development of kidney abnormalities related to hyperglycemia. The nuclear factor erythroid 2-related factor-2 (Nrf2) plays a crucial role in defending cells against oxidative stress by activating genes that produce antioxidants. L-sulforaphane (SFN), a drug that activates Nrf2, reduces damage caused by hyperglycemia. Hyperglycemic Wistar rats and HEK 293 cells maintained in hyperglycemic medium exhibited decreased Nrf2 nuclear translocation and reduced expression and activity of antioxidant enzymes. SFN treatment increased Nrf2 activity and reversed decreased renal function, oxidative stress and cell death associated with hyperglycemia. To investigate mechanisms involved in hyperglycemia-induced reduced Nrf2 activity, we addressed whether Nrf2 is modified by O-linked ß-N-acetylglucosamine (O-GlcNAc), a post-translational modification that is fueled in hyperglycemic conditions. In vivo, hyperglycemia increased O-GlcNAc-modified Nrf2 expression. Increased O-GlcNAc levels, induced by pharmacological inhibition of OGA, decreased Nrf2 activity in HEK 293 cells. In conclusion, hyperglycemia reduces Nrf2 activity, promoting oxidative stress, cell apoptosis and structural and functional renal damage. Pharmacological treatment with SFN attenuates renal injury. O-GlcNAcylation negatively modulates Nrf2 activity and represents a potential mechanism leading to oxidative stress and renal damage in hyperglycemic conditions.


Asunto(s)
Hiperglucemia , Enfermedades Renales , Animales , Humanos , Ratas , Antioxidantes/metabolismo , Apoptosis , Células HEK293 , Hiperglucemia/complicaciones , Hiperglucemia/metabolismo , Riñón/metabolismo , Enfermedades Renales/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Ratas Wistar , Sulfóxidos
18.
Parasit Vectors ; 16(1): 415, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37964392

RESUMEN

BACKGROUND: Tick control is a worldwide challenge due to its resistance to acaricides. Essential oils (EOs) and isolated compounds (EOCs) are potential alternatives for tick control technologies. METHODS: A review with EOs and EOCs, under field and semi-field conditions, was performed based on Scopus, Web of Science and PubMed databases. Thirty-one studies published between 1991 and 2022 were selected. The search was performed using the following keywords: "essential oil" combined with "tick," "Ixodes," "Argas," "Rhipicephalus," "Amblyomma," "Hyalomma," "Dermacentor," "Haemaphysalis" and "Ornithodoros." The words "essential oil" and "tick" were searched in the singular and plural. RESULTS: The number of studies increased over the years. Brazil stands out with the largest number (51.6%) of publications. The most studied tick species were Rhipicephalus microplus (48.4%), Ixodes scapularis (19.4%), Amblyomma americanum and R. sanguineus sensu lato (9.7% each). Cattle (70%) and dogs (13%) were the main target animal species. Regarding the application of EOs/EOCs formulations, 74% of the studies were conducted with topical application (spray, pour-on, foam, drop) and 26% with environmental treatment (spray). Efficacy results are difficult to evaluate because of the lack of information on the methodology and standardization. The nanotechnology and combination with synthetic acaricides were reported as an alternative to enhance the efficacy of EOs/EOCs. No adverse reactions were observed in 86.6% of the studies evaluating EOs/EOCs clinical safety. Studies regarding toxicity in non-target species and residues are scarce. CONCLUSIONS: This article provides a comprehensive review on the use of EOs and EOCs to reduce tick infestations, in both the hosts and the environment. As future directions, we recommend the chemical characterization of EOs, methodology standardization, combination of EOs/EOCs with potential synergists, nanotechnology for new formulations and safety studies for target and non-target organisms, also considering the environmental friendliness.


Asunto(s)
Acaricidas , Enfermedades de los Bovinos , Enfermedades de los Perros , Ixodes , Ixodidae , Aceites Volátiles , Rhipicephalus , Infestaciones por Garrapatas , Animales , Perros , Bovinos , Aceites Volátiles/química , Acaricidas/farmacología , Acaricidas/uso terapéutico , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/prevención & control , Infestaciones por Garrapatas/veterinaria , Amblyomma , Control de Ácaros y Garrapatas/métodos , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Perros/tratamiento farmacológico
19.
JAMA Netw Open ; 6(11): e2345138, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38032640

RESUMEN

Importance: Depression is a leading cause of disability worldwide, and there is increasing interest in nonpharmacological treatments. Auricular acupuncture (AA) is a simple, low-cost, and well-tolerated option, but further studies are needed to establish its efficacy and safety. Objective: To estimate the efficacy and safety of auricular acupuncture as a treatment for depression. Design, Setting, and Participants: This randomized clinical trial was conducted at 4 university research centers in Brazil, from March to July 2023. Eligible patients were adults aged 18 to 50 years whose score on the Patient Health Questionnaire-9 (PHQ-9) indicated moderate depression (score 10-14) or moderately severe depression (score 15-19). Exclusion criteria included previous application of AA, risk of suicidal ideation, or severe depression (PHQ-9 score >20). An intent-to-treat analysis and modified intent-to-treat analysis were conducted. Intervention: Participants were randomized into 2 treatment groups, which included specific AA (SA) and nonspecific AA (NSA). Both groups received 12 sessions of AA with semipermanent needles with daily stimulation twice a week over 6 weeks and were followed-up for 3 months. All participants continued with their usual care for ethical reasons. The SA group's treatment protocol consisted of 6 acupuncture points on the auricular pavilion chosen according to the diagnosis of depression by traditional Chinese medicine (Shenmen, subcortex, heart, lung, liver, and kidney). The NSA group's acupuncture points were the external ear, the cheek and face area, and 4 nonspecific points in the helix region unassociated with mental health symptoms. A locator device was used to confirm which areas had neuroreactive points. Main Outcomes and Measures: The primary outcome was a reduction of at least 50% in the PHQ-9 score (ie, depression recovery) at 3 months. Secondary outcomes included depression recovery at 4 and 6 weeks; depression remission (PHQ-9 score < 5) at 4 weeks, 6 weeks, and 3 months); and adverse events. Results: A total of 304 participants were screened, and 74 participants (62 women [84%]; median [IQR] age, 29 [23-27] years) were included in the intention-to-treat analysis, with 37 participants randomized to each group (SA and NSA). A total of 47 participants (64%) were followed-up through 3 months. The results showed no statistically significant difference in depressive recovery between the groups at 3 months (14 of 24 participants in the SA group [58%] vs 10 of 23 participants in the NSA group [43%]; risk ratio [RR], 1.34; 95% CI, 0.76-2.45; P = .38). The proportions of depression recovery and remission at 4 and 6 weeks based on the PHQ-9 were higher in the SA group (except for depression recovery at 6 weeks) with no statistically significant differences. However, a statistically significant difference was observed in symptom remission at 3 months (11 of 24 participants in the SA group [46%] vs 3 of 23 participants in the NSA group [13%]; RR, 1.99; 95% CI, 1.16-3.34; P = .02) in favor of SA. There were no significant differences in adverse event rates between the groups, evidencing the intervention's safety. Most participants reported mild pain at the needle application site (33 patients [94%] in the SA group vs 32 patients [91%] in the NSA group). Five participants dropped out of the study due to adverse events. Conclusions and Relevance: The results of this randomized clinical trial suggest that SA over 6 weeks is safe. Although there was no statistically significant difference between groups for the primary efficacy outcome, patients receiving SA did experience greater symptom remission at 3 months. A larger sample size and longer intervention are needed to further evaluate the efficacy of SA for depression. Trial Registration: ClinicalTrials.gov Identifier: NCT05855421.


Asunto(s)
Terapia por Acupuntura , Acupuntura Auricular , Trastorno Depresivo , Adulto , Humanos , Femenino , Depresión/terapia , Brasil
20.
Chem Commun (Camb) ; 59(84): 12641-12644, 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37791917

RESUMEN

We report the development of the first metallo-PROTAC, specifically a Pt-PROTAC, that can effectively degrade select Pt(II)-binding proteins. The Pt-PROTAC prototype successfully degraded thioredoxin-1 and thioredoxin reductase-1 in multiple myeloma cancer cell lines. Metallo-PROTACs will have important applications in the identification of metal binding proteins and as chemotherapeutic agents.


Asunto(s)
Proteínas Portadoras , Neoplasias , Humanos , Proteolisis , Proteínas
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