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1.
Vet Parasitol ; 324: 110069, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37984155

RESUMO

Although ivermectin (IVM) has a wide spectrum and long half-life, its frequent use as an anthelmintic for the last 42 years led to its worldwide tolerance by Haemonchus contortus. We evaluated the combination of limonene (LIM), a P-glycoprotein (Pgp) modulator, with IVM in lambs infected with a multidrug-resistant H. contortus. Twenty-four male Dorper lambs were artificially infected with two doses (seven days apart) of 8000 infective larvae of a multidrug-resistant isolate of H. contortus. The infection was patent 25 days later. Fifteen days before treatment with IVM (DAY -15), animals were divided into 4 groups: Infected-untreated control (CTL), IVM, LIM, and LIM+IVM. From DAY -15 to DAY + 14, groups LIM and LIM+IVM received 200 mg/kg of body weight/day of LIM via oral. On DAY 0, a single dose of IVM at 200 µg/kg of body weight was administered orally to groups IVM and LIM+IVM. On DAY + 7 and DAY + 14, fecal egg counts (FEC) were performed and on DAY + 14 animals were euthanized for total worm count (TWC), worm length, fecundity of females, and Pgp-9 gene expression. On DAY + 7, group LIM+IVM had 96.29% efficacy based on Fecal Egg Count Reduction TEST (FECRT) and a highly significant reduction in FEC (P = 0.0005) when compared to CTL. On DAY + 14, the efficacy of LIM+IVM was 82.87% on FECRT, although no differences were found among groups for FEC, TWC, worm length, or Pgp-9 gene expression. Female worms from the CTL group had higher egg counts in their uterus when compared to LIM. No differences were found for hematological or biochemical parameters, body weight, or weight gain among groups. Thus, LIM given daily at 200 mg/kg was safe for animals and, when combined with IVM, decreased egg shedding and could reduce pasture contamination, although it was unable to kill multidrug-resistant H. contortus.


Assuntos
Anti-Helmínticos , Hemoncose , Haemonchus , Doenças dos Ovinos , Ovinos , Animais , Feminino , Masculino , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Haemonchus/genética , Limoneno/farmacologia , Óvulo , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Carneiro Doméstico , Peso Corporal , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Expressão Gênica , Hemoncose/tratamento farmacológico , Hemoncose/veterinária , Doenças dos Ovinos/tratamento farmacológico , Fezes , Contagem de Ovos de Parasitas/veterinária
2.
Public Health ; 217: 212-217, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36924673

RESUMO

OBJECTIVES: Examine differences in multidimensional well-being from before (January 2020) to three timepoints during the COVID-19 pandemic (June 2020, January 2021, January 2022). STUDY DESIGN: Repeated cross-sectional design. METHODS: Nationally representative cross-sectional cohorts of US adults completed the Secure Flourish Index before (January 2020 cohort: N = 1010) and during the COVID-19 pandemic (June 2020 cohort: N = 3020; January 2021 cohort: N = 3366; January 2022 cohort: N = 2598). We estimated differences in indicators, domains, and composite well-being between the January 2020 cohort and each of the subsequent cohorts. We also explored whether changes in well-being between January 2020 and January 2022 varied based on age, gender, and race/ethnicity. RESULTS: Initial declines in well-being observed by June 2020 were largely followed by a return to prepandemic levels in January 2022, with some exceptions. Notably, general declines in mental health have persisted through to January 2022. On the other hand, there was evidence of general improvements in character & virtue that exceeded prepandemic levels in January 2022. Young adults and racial/ethnic minorities reported lower financial & material stability in January 2022 compared to before the COVID-19 pandemic. CONCLUSIONS: Although there are promising signs that the well-being of US adults has mostly recovered to prepandemic levels, a coordinated response is urgently needed to support population mental health and the financial security of vulnerable groups. As society continues the journey toward postpandemic recovery, continued tracking of multidimensional well-being will be important for making informed decisions about public health priorities.


Assuntos
COVID-19 , Adulto Jovem , Humanos , Estados Unidos/epidemiologia , COVID-19/epidemiologia , Estudos Transversais , Pandemias , Tomada de Decisões , Etnicidade
3.
Bioorg Med Chem ; 27(8): 1449-1455, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30528164

RESUMO

Extracellular adenosine 5'-triphosphate (ATP) triggers the P2X7 receptor (P2X7R) ionic channel to stimulate the release of the interleukin-IL-1ß cytokine into macrophages. The current study explored the reaction of six structurally diverse triazole derivatives on P2X7-mediated dye uptake into murine peritoneal macrophages. P2X7R activity determined by ATP-evoked fluorescent dye uptake. Triazole derivatives toxicity measured using dextran rhodamine exclusion based colorimetric assay. A740004 and BBG, both P2X7R antagonist, inhibited ATP-induced dye uptake. In contrast, the derivatives 5a, 5b, 5e, and 5f did not diminish P2X7R activity in concentrations until 100 µM. 5c and 5d analogs caused a potent inhibitory activity on P2X7-induced dye uptake. Dextran Rhodamine exclusion measurements after 24 h of continuous treatment with triazole derivatives indicated a moderated toxicity for all molecules. In conclusion, this study showed that a series of new hybrid 1,2,3-triazolic naphthoquinones reduces P2X7R-induced dye uptake into murine macrophages. In silico analysis indicates a good pharmacokinetic profile and molecular docking results of these analogs indicate the potential to bind into an allosteric site located into the P2X7R pore and juxtaposed with the ATP binding pocket. In this manner, the compounds 5c and 5d may be used as a scaffold for new P2X7R inhibitors with reduced toxicity, and good anti-inflammatory activity.


Assuntos
Naftoquinonas/química , Antagonistas do Receptor Purinérgico P2X/química , Receptores Purinérgicos P2X7/metabolismo , Triazóis/química , Sítio Alostérico , Animais , Sítios de Ligação , Células CACO-2 , Linhagem Celular , Corantes/metabolismo , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Permeabilidade/efeitos dos fármacos , Estrutura Terciária de Proteína , Antagonistas do Receptor Purinérgico P2X/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X7/química , Triazóis/metabolismo , Triazóis/farmacologia
4.
J Bioenerg Biomembr ; 50(4): 307-313, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29882206

RESUMO

Purinergic receptors are widespread in the human organism and are involved in several physiological functions like neurotransmission, nociception, platelet aggregation, etc. In the immune system, they may regulate the expression and release of pro-inflammatory factors as well as the activation and death of several cell types. It is already described the participation of some purinergic receptors in the inflammation and pathological processes, such as a few neglected tropical diseases (NTDs) which affect more than 1 billion people in the world. Although the high social influence those diseases represent endemic countries, most of them do not have an efficient, safe or affordable drug treatment. In that way, this review aims to discuss the current literature involving purinergic receptor and immune response to NTDs pathogens, which may contribute in the search for new therapeutic possibilities.


Assuntos
Doenças Negligenciadas/tratamento farmacológico , Receptores Purinérgicos/metabolismo , Medicina Tropical/métodos , Animais , Humanos , Imunidade , Inflamação , Terapia de Alvo Molecular/métodos , Doenças Negligenciadas/imunologia , Doenças Negligenciadas/patologia , Transdução de Sinais/efeitos dos fármacos
5.
Parasitol Res ; 117(3): 705-712, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29327323

RESUMO

Albendazole (ABZ), a benzimidazole widely used to control gastrointestinal parasites, is poorly soluble in water, resulting in variable and incomplete bioavailability. This has favored the appearance ABZ-resistant nematodes and, consequently, an increase in its clinical ineffectiveness. Among the pharmaceutical techniques developed to increase drug efficacy, cyclodextrins (CDs) and other polymers have been extensively used with water-insoluble pharmaceutical drugs to increase their solubility and availability. Our objective was to prepare ABZ formulations, including ß-cyclodextrin (ßCD) or hydroxypropyl-ß-cyclodextrin (HPßCD), associated or not to the water-soluble polymer polyvinylpyrrolidone (PVP). These formulations had their solubility and anthelmintic effect both evaluated in vitro. Also, their anthelmintic efficacy was evaluated in lambs naturally infected with gastrointestinal nematodes (GIN) through the fecal egg count (FEC) reduction test. In vitro, the complex ABZ/HPßCD had higher solubility than ABZ/ßCD. The addition of PVP to the complexes increased solubility and dissolution rates more effectively for ABZ/HPßCD than for ABZ/ßCD. In vivo, 48 lambs naturally infected with GIN were divided into six experimental groups: control, ABZ, ABZ/ßCD, ABZ/ßCD-PVP, ABZ/HPßCD, and ABZ/HPßCD-PVP. Each treated animal received 10 mg/kg of body weight (based on the ABZ dose) for three consecutive days. After 10 days of the last administered dose, treatment efficacy was calculated. The efficacy values were as follows: ABZ (70.33%), ABZ/ßCD (85.33%), ABZ/ßCD-PVP (82.86%), ABZ/HPßCD (78.37%), and ABZ/HPßCD-PVP (43.79%). In vitro, ABZ/HPßCD and ABZ/HPßCD-PVP had high solubility and dissolution rates. In vivo, although the efficacies of ABZ/ßCD, ABZ/ßCD-PVP, and ABZ/HPßCD increased slightly when compared to pure ABZ, this increase was not significant (P > 0.05).


Assuntos
Albendazol/farmacocinética , Antiparasitários/farmacocinética , Ciclodextrinas/farmacocinética , Nanopartículas/química , Povidona/farmacocinética , 2-Hidroxipropil-beta-Ciclodextrina/química , 2-Hidroxipropil-beta-Ciclodextrina/farmacocinética , Albendazol/química , Animais , Anti-Helmínticos/química , Anti-Helmínticos/farmacocinética , Antiparasitários/química , Disponibilidade Biológica , Ciclodextrinas/química , Composição de Medicamentos , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/veterinária , Masculino , Nematoides , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/veterinária , Povidona/química , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Solubilidade , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacocinética
6.
Vet Parasitol ; 246: 118-123, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28969774

RESUMO

Haemonchus contortus is the most important nematode in small ruminant systems, and has developed tolerance to all commercial anthelmintics in several countries. In vitro (egg hatch assay) and in vivo tests were performed with a multidrug strain of Haemonchus contortus using Terminalia catappa leaf, fruit pulp, and seed extracts (in vitro), or pulp and seed powder in lambs experimentally infected with H. contortus. Crude extracts from leaves, fruit pulp and seeds obtained with 70% acetone were lyophilized until used. In vitro, the extracts had LC50=2.48µg/mL (seeds), LC50=4.62µg/mL (pulp), and LC50=20µg/mL (leaves). In vitro, seed and pulp extracts had LC50 similar to Thiabendazole (LC50=1.31µg/mL). Condensed tannins were more concentrated in pulp extract (183.92g of leucocyanidin/kg dry matter) than in either leaf (4.6g) or seed (35.13g) extracts. Phytochemical tests established that all extracts contained alkaloids, flavonoids, saponins, phenols, and terpenoids. Based on these results, in vivo tests were performed to evaluate the anthelmintic activity of T. catappa whole fruit (pulp+seed) powder. Male Santa Ines lambs were artificially infected with multidrug-resistant H. contortus and divided, according to similar fecal egg count (FEC) and weight, into two groups: Control (infected/untreated) and treated (infected/treated with whole fruit powder). Whole fruit powder was mixed with concentrate and provided at 2g/kg of body weight (BW) for five days. After treatment, parasitological analysis (FEC and egg hatch assay), renal profile (urea and creatinine), liver profile (aspartate aminotransferase) and BW were determined. In vitro (based on LC50), seed/pulp extracts had ovicidal effect similar to Thiabendazole but whole fruit powder had no anthelmintic effect on adult nematodes in the abomasum. We discuss the plausible causes of the lack of in vivo activity.


Assuntos
Hemoncose/tratamento farmacológico , Hemoncose/veterinária , Extratos Vegetais/uso terapêutico , Doenças dos Ovinos/parasitologia , Terminalia/química , Animais , Anti-Helmínticos/uso terapêutico , Frutas , Haemonchus/efeitos dos fármacos , Masculino , Contagem de Ovos de Parasitas/veterinária , Fitoterapia , Extratos Vegetais/química , Folhas de Planta/química , Sementes/química , Ovinos , Doenças dos Ovinos/tratamento farmacológico
7.
An Sist Sanit Navar ; 39(3): 389-397, 2016 12 30.
Artigo em Espanhol | MEDLINE | ID: mdl-28032874

RESUMO

Objective. To analyze transport accident mortality trends in Navarra, a region in the North of Spain, between 1999 and 2013 and assess the effect of the Demerit Point System. Methods. Cause of death coding was done according to ICD-10 with information from the medical death certificate and forensic reports. Mortality rates by age, sex, type of victim and residence (urban/rural) were calculated. We performed an ARIMA Box and Jenkins analysis to estimate the effect on mortality rates due to transport accidents of the Demerit Point System, which had been introduced in Spain in July 2006. Results. From January 1st 1999 to December 31st 2013, 1,052 deaths were registered, 1,044 of which were from accidents involving ground transport vehicles (1,020 from road traffic accidents and 24 from non-road traffic accidents). Mortality rates were higher in men and people aged 18-24 and 65-84. Most of the deaths amongst younger men and adults occurred in drivers, while fatalities occurring in those older than 84 years were mostly in pedestrians. Men and women living in rural areas had a mortality risk from transport accident 33% and 21% higher than people living in urban areas. Since the introduction of the Demerit Point System, mortality rates have fallen by 51%. Conclusions. Mortality statistics for Navarra show the effectiveness of preventive strategies designed in Spain during recent years.


Assuntos
Acidentes/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Veículos Automotores , Espanha/epidemiologia , Fatores de Tempo , Adulto Jovem
8.
Gastroenterol Clin North Am ; 30(3): 709-33, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11586554

RESUMO

Colitic infection caused by a variety of organisms may have an extremely varied presentation, course, and treatment response. Current data have provided great insights into the pathophysiology of these various organisms and their clinical presentation, course, and treatment outcomes. As clinicians develop a better understanding of the colon, its immunologic defense mechanisms, and the virulence factors of such organisms, they will be better able to evaluate these infections as well as newer colonic infections yet unknown. It is important to know if and when to treat such organisms to prevent the dilemma of drug-resistant strains, as seen already in a variety of well-known infections, such as Campylobacter and others. Knowledge of such colonic targets will be more important in an era of ever-growing resistance to and wide use of antibiotic regimens.


Assuntos
Infecções Bacterianas/microbiologia , Enterocolite/microbiologia , Infecções Bacterianas/complicações , Humanos
9.
AIDS Res Hum Retroviruses ; 16(12): 1157-62, 2000 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-10954891

RESUMO

Cytomegalovirus (CMV) can be an important opportunistic infection in HIV-1-infected patients, particularly when the CD4+ T-cell count drops below 50 lymphocytes/mm3. CMV-associated disease, including retinitis, pneumonitis, gastroenteritis, and encephalitis, is estimated to affect up to 40% of AIDS patients. We have studied the cellular immune response to CMV in gut-associated lymphoid tissue (GALT) of HIV-1-infected patients. Two patients with chronic diarrhea of unknown etiology were examined by flexible sigmoidoscopy and upper endoscopy. Biopsy specimens were obtained from lymphoid-associated tissue sites in rectum and duodenum. Both patients were seropositive for CMV IgG, but had not been treated with ganciclovir, and neither had clinical signs of CMV disease. Mononuclear cell cultures were established from GALT and blood and assayed for the presence of CMV-specific CD8+ T cells. CD8+ T-cell phenotype and function were assessed by MHC Class I tetramer staining, using an HLA-A*0201 tetramer complex specific for peptide 495-503 (NLVPMVATV) of CMV lower matrix protein pp65, and by a standard 51Cr release assay. CMV pp65-specific cytotoxic lymphocytes (CTL) were detected in GALT and blood MNC from both patients. These results demonstrate that HIV-1-infected subjects seropositive for CMV, but without active CMV gastrointestinal disease, harbor CMV-specific CTL in intestinal lymphoid tissue. This is the first report of isolation of CMV-specific CTL in GALT and will lead to greater understanding of the pathogenesis of CMV disease in human mucosal tissue.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Infecções por HIV/imunologia , Mucosa Intestinal/imunologia , Tecido Linfoide/imunologia , Linfócitos T Citotóxicos/imunologia , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/patologia , Antígenos CD/análise , Citotoxicidade Imunológica , Duodeno , Infecções por HIV/complicações , Infecções por HIV/patologia , Humanos , Imunofenotipagem , Mucosa Intestinal/patologia , Ativação Linfocitária , Tecido Linfoide/patologia , Masculino , Pessoa de Meia-Idade , Reto , Linfócitos T Citotóxicos/patologia
10.
Virology ; 270(2): 317-27, 2000 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-10792991

RESUMO

Acute HIV-1 infection depletes CD4(+) T cells in gut-associated lymphoid tissue (GALT). The failure of containment of local viral replication, and consequent CD4(+) T cell depletion, might be due to delayed mobilization of effector CD8(+) T cells or absence of functioning HIV-1-specific CD8(+) T cell effectors within GALT. No studies have addressed human intestinal HIV-1-specific CD8(+) T cell functions. We sought to determine whether functional HIV-1-specific CTL were present in GALT and whether the repertoire differed from HIV-1-specific CTL isolated from peripheral blood mononuclear cells. From three HIV-1-infected subjects, we isolated HIV-1-specific CD8(+) T cells expressing the mucosal lymphocyte integrin CD103 from GALT. These antigen-specific effector cells could be expanded in vitro and lysed target cells in an MHC class I-restricted manner. HIV-1-specific CTL could be isolated from both duodenal and rectal GALT sites, indicating that CD8(+) effectors were widespread through GALT tissue. The breadth and antigenic specificities of GALT CTL appeared to differ from those in peripheral blood in some cases. In summary, we found HIV-1-specific CD8(+) effector T cells in GALT, despite HIV-1-induced CD4(+) T cell lymphopenia. This suggests that HIV-1-specific CTL in gut tissue can be maintained with limited CD4(+) T cell help.


Assuntos
Antígenos CD/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/isolamento & purificação , Imunidade nas Mucosas/imunologia , Cadeias alfa de Integrinas , Adulto , Apresentação de Antígeno , Citotoxicidade Imunológica , Duodeno/imunologia , Duodeno/virologia , Antígenos HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Reto/imunologia , Reto/virologia
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