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1.
J Pharmacol Exp Ther ; 390(1): 65-77, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38772718

RESUMEN

The high prevalence of breast cancer is a global health concern, compounded by the lack of safe or effective treatments for its advanced stages. These facts urge the development of novel treatment strategies. Annexin A5 (ANXA5) is a natural human protein that binds with high specificity to phosphatidylserine, a phospholipid tightly maintained in the inner leaflet of the cell membrane on most healthy cells but externalized in tumor cells and the tumor vasculature. Here, we have developed a targeted photosensitizer for photothermal therapy (PTT) of solid tumors through the functionalization of single-walled carbon nanotubes (SWCNTs) to ANXA5-the SWCNT-ANXA5 conjugate. The ablation of tumors through the SWCNT-ANXA5-mediated PTT synergizes with checkpoint inhibition, creating a systemic anticancer immune response. In vitro ablation of cells incubated with the conjugate promoted cell death in a dose-dependent and targeted manner. This treatment strategy was tested in vivo with the orthotopic EMT6 breast tumor model in female balb/cJ mice. Enhanced therapeutic effects were achieved by using intratumoral injection of the conjugate and treating tumors at a lower PTT temperature (45°C). Intratumoral injection prevented the accumulation of the SWCNTs in major clearance organs. When combined with checkpoint inhibition of anti-programmed cell death protein-1, SWCNT-ANXA5-mediated PTT increased survival and 80% of the mice survived for 100 days. Evidence of immune system activation by flow cytometry of splenic cells strengthens the hypothesis of an abscopal effect as a mechanism of prolonged survival. SIGNIFICANCE STATEMENT: This study demonstrated a relatively high survival rate (80% at 100 days) of mice with aggressive breast cancer when treated with photothermal therapy using the SWCNT-ANXA5 conjugate injected intratumorally and combined with immune stimulation using the anti-programmed cell death protein-1 checkpoint inhibitor. Photothermal therapy was accomplished by maintaining the tumor temperature at a relatively low level of 45°C and avoiding accumulation of the nanotubes in the clearance organs by using intratumoral administration.


Asunto(s)
Neoplasias de la Mama , Ratones Endogámicos BALB C , Nanotubos de Carbono , Terapia Fototérmica , Nanotubos de Carbono/química , Animales , Femenino , Ratones , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Neoplasias de la Mama/inmunología , Terapia Fototérmica/métodos , Línea Celular Tumoral , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Humanos , Metástasis de la Neoplasia , Inmunoterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Fototerapia/métodos
2.
Rev Neurol (Paris) ; 180(5): 410-416, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38609751

RESUMEN

Genetic cerebellar ataxias are still a diagnostic challenge, and yet not all of them have been identified. Very recently, in early 2023, a new cause of late-onset cerebellar ataxia (LOCA) was identified, spinocerebellar ataxia 27B (SCA27B). This is an autosomal dominant ataxia due to a GAA expansion in intron 1 of the FGF14 gene. Thanks to the many studies carried out since its discovery, it is now possible to define the clinical phenotype, its particularities, and the progression of SCA27B. It has also been established that it is one of the most frequent causes of LOCA. The core phenotype of the disease consists of slowly progressive late-onset ataxia with cerebellar syndrome, oculomotor disorders including downbeat nystagmus, and episodic symptoms such as diplopia. Therapeutic approaches have been proposed, including acetazolamide, and 4-aminopyridine, the latter with a better benefit/tolerance profile.


Asunto(s)
Degeneraciones Espinocerebelosas , Degeneraciones Espinocerebelosas/diagnóstico por imagen , Degeneraciones Espinocerebelosas/genética , Degeneraciones Espinocerebelosas/terapia , Factores de Crecimiento de Fibroblastos , Intrones , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética
3.
Rev Neurol (Paris) ; 180(1-2): 79-93, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38216420

RESUMEN

Autonomic failure is frequently encountered in synucleinopathies such as multiple system atrophy (MSA), Parkinson's disease (PD), Lewy body disease, and pure autonomic failure (PAF). Cardiovascular autonomic failure affects quality of life and can be life threatening due to the risk of falls and the increased incidence of myocardial infarction, stroke, and heart failure. In PD and PAF, pathogenic involvement is mainly post-ganglionic, while in MSA, the involvement is mainly pre-ganglionic. Cardiovascular tests exploring the autonomic nervous system (ANS) are based on the analysis of continuous, non-invasive recordings of heart rate and digital blood pressure (BP). They assess facets of sympathetic and parasympathetic activities and provide indications on the integrity of the baroreflex arc. The tilt test is widely used in clinical practice. It can be combined with catecholamine level measurement and analysis of baroreflex activity and cardiac variability for a detailed analysis of cardiovascular damage. MIBG myocardial scintigraphy is the most sensitive test for early detection of autonomic dysfunction. It provides a useful measure of post-ganglionic sympathetic fiber integrity and function and is therefore an effective tool for distinguishing PD from other parkinsonian syndromes such as MSA. Autonomic cardiovascular investigations differentiate between certain parkinsonian syndromes that would otherwise be difficult to segregate, particularly in the early stages of the disease. Exploring autonomic failure by gathering information about residual sympathetic tone, low plasma norepinephrine levels, and supine hypertension can guide therapeutic management of orthostatic hypotension (OH).


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo , Atrofia de Múltiples Sistemas , Enfermedad de Parkinson , Insuficiencia Autonómica Pura , Sinucleinopatías , Humanos , Insuficiencia Autonómica Pura/complicaciones , Insuficiencia Autonómica Pura/diagnóstico , Insuficiencia Autonómica Pura/terapia , Sinucleinopatías/complicaciones , Calidad de Vida , Enfermedades del Sistema Nervioso Autónomo/diagnóstico , Enfermedades del Sistema Nervioso Autónomo/etiología , Enfermedades del Sistema Nervioso Autónomo/terapia , Atrofia de Múltiples Sistemas/complicaciones , Atrofia de Múltiples Sistemas/diagnóstico , Atrofia de Múltiples Sistemas/terapia , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/terapia
4.
Phys Chem Chem Phys ; 25(22): 15463-15468, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37249180

RESUMEN

The synthesis and characterisation of a bis(iminium)phenoxide diacid cation [4-tBu-C6H2-2,6-(HCN(H)Dipp)-1-O]+ ([H2tBu,DippL]+), is discussed. [H2tBu,DippL][BF4] (1) and [H2tBu,DippL][H2N{B(C6F5)3}2] (2) were synthesised in high yields via protonation of the bis(imino)phenol conjugate base with ethereal HBF4 or Bochmann's acid ([H(OEt2)2][H2N{B(C6F5)3}2]). Both species were fully characterised using NMR and IR spectroscopy as well as X-ray crystallography. The cationic fragment adopts an unusual tautomeric form in which both acidic protons are located on the nitrogen atoms: [HN〈O〉NH]+. This bis(iminium) phenoxide tautomer is stabilised by delocalisation of electron density from oxygen, into the extended π-system of the planar cation, and was found to be 22.6 and 263.1 kJ mol-1 lower in energy (ΔG) than the alternative [N〈OH〉NH]+ and [N〈OH2〉N]+ tautomers respectively. Topological analysis confirmed the presence of two electrostatic N+H⋯O- hydrogen bonds which contribute -111.2 kJ mol-1 towards the stabilisation of the diacid. The pKa values of the cations were estimated, from NMR experiments, to be 4.2 in THF (1) and 11.4 in acetonitrile (2).

5.
Int J Mol Sci ; 24(10)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37240430

RESUMEN

Diabetes mellitus (DM) is a serious chronic metabolic disease that is associated with hyperglycemia and several complications including cardiovascular disease and chronic kidney disease. DM is caused by high levels of blood sugar in the body associated with the disruption of insulin metabolism and homeostasis. Over time, DM can induce life-threatening health problems such as blindness, heart disease, kidney damage, and stroke. Although the cure of DM has improved over the past decades, its morbidity and mortality rates remain high. Hence, new therapeutic strategies are needed to overcome the burden of this disease. One such prevention and treatment strategy that is easily accessible to diabetic patients at low cost is the use of medicinal plants, vitamins, and essential elements. The research objective of this review article is to study DM and explore its treatment modalities based on medicinal plants and vitamins. To achieve our objective, we searched scientific databases of ongoing trials in PubMed Central, Medline databases, and Google Scholar websites. We also searched databases on World Health Organization International Clinical Trials Registry Platform to collect relevant papers. Results of numerous scientific investigations revealed that phytochemicals present in medicinal plants (Allium sativum, Momordica charantia, Hibiscus sabdariffa L., and Zingiber officinale) possess anti-hypoglycemic activities and show promise for the prevention and/or control of DM. Results also revealed that intake of vitamins C, D, E, or their combination improves the health of diabetes patients by reducing blood glucose, inflammation, lipid peroxidation, and blood pressure levels. However, very limited studies have addressed the health benefits of medicinal plants and vitamins as chemo-therapeutic/preventive agents for the management of DM. This review paper aims at addressing this knowledge gap by studying DM and highlighting the biomedical significance of the most potent medicinal plants and vitamins with hypoglycemic properties that show a great potential to prevent and/or treat DM.


Asunto(s)
Diabetes Mellitus , Plantas Medicinales , Humanos , Plantas Medicinales/química , Vitaminas/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Glucemia/metabolismo , Vitamina A/uso terapéutico , Vitamina K
6.
Emerg Infect Dis ; 28(1): 205-209, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34807815

RESUMEN

Severe acute respiratory syndrome coronavirus 2 Delta variant epidemiology in Africa is unknown. We found Delta variant was introduced in Benin during April-May 2021 and became predominant within 2 months, after which a steep increase in reported coronavirus disease incidence occurred. Benin might require increased nonpharmaceutical interventions and vaccination coverage.


Asunto(s)
COVID-19 , SARS-CoV-2 , Benin/epidemiología , Humanos
7.
Bioessays ; 42(5): e1900220, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32301149

RESUMEN

Indoleamine 2,3-dioxygenase (IDO) is the rate-limiting enzyme in conversion of tryptophan to kynurenines, feeding de novo nicotinamide synthesis. IDO orchestrates materno-foetal tolerance, increasing human reproductive fitness. IDO mediates immune suppression through depletion of tryptophan required by T lymphocytes and other mechanisms. IDO is expressed by alternatively activated macrophages, suspected to play a key role in tuberculosis (TB) pathogenesis. Unlike its human host, Mycobacterium tuberculosis can synthesize tryptophan, suggesting possible benefit to the host from infection with the microbe. Intriguingly, nicotinamide analogues are used to treat TB. In reviewing this field, it is postulated that flux through the nicotinamide synthesis pathway reflects switching between aerobic glycolysis and oxidative phosphorylation in M. tuberculosis-infected macrophages. The evolutionary cause of such shifts may be ancient mitochondrial behavior related to reproductive fitness. Evolutionary perspectives on the IDO pathway may elucidate why, after centuries of co-existence with the Tubercle bacillus, humans still remain susceptible to TB disease.


Asunto(s)
Indolamina-Pirrol 2,3,-Dioxigenasa , Tuberculosis , Catálisis , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Macrófagos , Niacinamida , Tuberculosis/genética
8.
Int J Mol Sci ; 23(3)2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35163459

RESUMEN

Cisplatin and other platinum-based drugs, such as carboplatin, ormaplatin, and oxaliplatin, have been widely used to treat a multitude of human cancers. However, a considerable proportion of patients often relapse due to drug resistance and/or toxicity to multiple organs including the liver, kidneys, gastrointestinal tract, and the cardiovascular, hematologic, and nervous systems. In this study, we sought to provide a comprehensive review of the current state of the science highlighting the use of cisplatin in cancer therapy, with a special emphasis on its molecular mechanisms of action, and treatment modalities including the combination therapy with natural products. Hence, we searched the literature using various scientific databases., such as MEDLINE, PubMed, Google Scholar, and relevant sources, to collect and review relevant publications on cisplatin, natural products, combination therapy, uses in cancer treatment, modes of action, and therapeutic strategies. Our search results revealed that new strategic approaches for cancer treatment, including the combination therapy of cisplatin and natural products, have been evaluated with some degree of success. Scientific evidence from both in vitro and in vivo studies demonstrates that many medicinal plants contain bioactive compounds that are promising candidates for the treatment of human diseases, and therefore represent an excellent source for drug discovery. In preclinical studies, it has been demonstrated that natural products not only enhance the therapeutic activity of cisplatin but also attenuate its chemotherapy-induced toxicity. Many experimental studies have also reported that natural products exert their therapeutic action by triggering apoptosis through modulation of mitogen-activated protein kinase (MAPK) and p53 signal transduction pathways and enhancement of cisplatin chemosensitivity. Furthermore, natural products protect against cisplatin-induced organ toxicity by modulating several gene transcription factors and inducing cell death through apoptosis and/or necrosis. In addition, formulations of cisplatin with polymeric, lipid, inorganic, and carbon-based nano-drug delivery systems have been found to delay drug release, prolong half-life, and reduce systemic toxicity while other formulations, such as nanocapsules, nanogels, and hydrogels, have been reported to enhance cell penetration, target cancer cells, and inhibit tumor progression.


Asunto(s)
Productos Biológicos/farmacología , Cisplatino/farmacología , Neoplasias/tratamiento farmacológico , Animales , Productos Biológicos/química , Productos Biológicos/uso terapéutico , Cisplatino/química , Cisplatino/uso terapéutico , Composición de Medicamentos , Sinergismo Farmacológico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes/efectos de los fármacos , Humanos
9.
Am J Primatol ; 83(1): e23213, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33169878

RESUMEN

Despite the large body of literature on ape conservation, much of the data needed for evidence-based conservation decision-making is still not readily accessible and standardized, rendering cross-site comparison difficult. To support knowledge synthesis and to complement the IUCN SSC Ape Populations, Environments and Surveys database, we created the A.P.E.S. Wiki (https://apeswiki.eva.mpg.de), an open-access platform providing site-level information on ape conservation status and context. The aim of this Wiki is to provide information and data about geographical ape locations, to curate information on individuals and organizations active in ape research and conservation, and to act as a tool to support collaboration between conservation practitioners, scientists, and other stakeholders. To illustrate the process and benefits of knowledge synthesis, we used the momentum of the update of the conservation action plan for western chimpanzees (Pan troglodytes verus) and began with this critically endangered taxon. First, we gathered information on 59 sites in West Africa from scientific publications, reports, and online sources. Information was compiled in a standardized format and can thus be summarized using a web scraping approach. We then asked experts working at those sites to review and complement the information (20 sites have been reviewed to date). We demonstrate the utility of the information available through the Wiki, for example, for studying species distribution. Importantly, as an open-access platform and based on the well-known wiki layout, the A.P.E.S. Wiki can contribute to direct and interactive information sharing and promote the efforts invested by the ape research and conservation community. The Section on Great Apes and the Section on Small Apes of the IUCN SSC Primate Specialist Group will guide and support the expansion of the platform to all small and great ape taxa. Similar collaborative efforts can contribute to extending knowledge synthesis to all nonhuman primate species.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Especies en Peligro de Extinción , Pan troglodytes , África Occidental , Animales
10.
Int J Mol Sci ; 21(12)2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32580345

RESUMEN

The treatment for ovarian cancers includes chemotherapies which use drugs such as cisplatin, paclitaxel, carboplatin, platinum, taxanes, or their combination, and other molecular target therapies. However, these current therapies are often accompanied with side effects. Vernonia calvoana (VC) is a valuable edible medicinal plant that is widespread in West Africa. In vitro data in our lab demonstrated that VC crude extract inhibits human ovarian cancer cells in a dose-dependent manner, suggesting its antitumor activity. From the VC crude extract, we have generated 10 fractions and VC fraction 7 (F7) appears to show the highest antitumor activity towards ovarian cancer cells. However, the mechanisms by which VC F7 exerts its antitumor activity in cancer cells remain largely unknown. We hypothesized that VC F7 inhibits cell proliferation and induces DNA damage and cell cycle arrest in ovarian cells through oxidative stress. To test our hypothesis, we extracted and fractionated VC leaves. The effects of VC F7 were tested in OVCAR-3 cells. Viability was assessed by the means of MTS assay. Cell morphology was analyzed by acridine orange and propidium iodide (AO/PI) dye using a fluorescent microscope. Oxidative stress biomarkers were evaluated by the means of lipid peroxidation, catalase, and glutathione peroxidase assays, respectively. The degree of DNA damage was assessed by comet assay. Cell cycle distribution was assessed by flow cytometry. Data generated from the MTS assay demonstrated that VC F7 inhibits the growth of OVCAR-3 cells in a dose-dependent manner, showing a gradual increase in the loss of viability in VC F7-treated cells. Data obtained from the AO/PI dye assessment revealed morphological alterations and exhibited characteristics such as loss of cellular membrane integrity, cell shrinkage, cell membrane damage, organelle breakdown, and detachment from the culture plate. We observed a significant increase (p < 0.05) in the levels of malondialdhyde (MDA) production in treated cells compared to the control. A gradual decrease in both catalase and glutathione peroxidase activities were observed in the treated cells compared to the control. Data obtained from the comet assay showed a significant increase (p < 0.05) in the percentages of DNA cleavage and comet tail length. The results of the flow cytometry analysis indicated VC F7 treatment caused cell cycle arrest at the S-phase checkpoint. Taken together, our results demonstrate that VC F7 exerts its anticancer activity by inhibiting cell proliferation, inducing DNA damage, and causing cell cycle arrest through oxidative stress in OVAR-3 cells. This finding suggests that VC F7 may be a potential alternative dietary agent for the prevention and/or treatment of ovarian cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Vernonia/química , Apoptosis , Ciclo Celular , Proliferación Celular , Ensayo Cometa , Daño del ADN , Femenino , Humanos , Neoplasias Ováricas/patología , Células Tumorales Cultivadas
11.
Am J Primatol ; 81(9): e23042, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31468565

RESUMEN

As animal populations continue to decline, frequently driven by large-scale land-use change, there is a critical need for improved environmental planning. While data-driven spatial planning is widely applied in conservation, as of yet it is rarely used for primates. The western chimpanzee (Pan troglodytes verus) declined by 80% within 24 years and was uplisted to Critically Endangered by the IUCN Red List of Threatened Species in 2016. To support conservation planning for western chimpanzees, we systematically identified geographic areas important for this taxon. We based our analysis on a previously published data set of modeled density distribution and on several scenarios that accounted for different spatial scales and conservation targets. Across all scenarios, typically less than one-third of areas we identified as important are currently designated as high-level protected areas (i.e., national park or IUCN category I or II). For example, in the scenario for protecting 50% of all chimpanzees remaining in West Africa (i.e., approximately 26,500 chimpanzees), an area of approximately 60,000 km2 was selected (i.e., approximately 12% of the geographic range), only 24% of which is currently designated as protected areas. The derived maps can be used to inform the geographic prioritization of conservation interventions, including protected area expansion, "no-go-zones" for industry and infrastructure, and conservation sites outside the protected area network. Environmental guidelines by major institutions funding infrastructure and resource extraction projects explicitly require corporations to minimize the negative impact on great apes. Therefore, our results can inform avoidance and mitigation measures during the planning phases of such projects. This study was designed to inform future stakeholder consultation processes that could ultimately integrate the conservation of western chimpanzees with national land-use priorities. Our approach may help in promoting similar work for other primate taxa to inform systematic conservation planning in times of growing threats.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Especies en Peligro de Extinción , Pan troglodytes , África Occidental , Animales
12.
Adv Exp Med Biol ; 1152: 31-49, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31456178

RESUMEN

Breast cancer is the most common noncutaneous malignancy and the second most lethal form of cancer among women in the United States. It currently affects more than one in ten women worldwide. The chance for a female to be diagnosed with breast cancer during her lifetime has significantly increased from 1 in 11 women in 1975 to 1 in 8 women (Altekruse, SEER Cancer Statistics Review, 1975-2007. National Cancer Institute, Bethesda, 2010). This chance for a female of being diagnosed with cancer generally increases with age (Howlader et al, SEER Cancer Statistics Review, 1975-2010. National Cancer Institute, Bethesda, 2013). Fortunately, the mortality rate from breast cancer has decreased in recent years due to increased emphasis on early detection and more effective treatments in the White population. Although the mortality rates have declined in some ethnic populations, the overall cancer incidence among African American and Hispanic population has continued to grow. The goal of the work presented in this book chapter is to highlight similarities and differences in breast cancer morbidity and mortality rates among non-Hispanic white and non-Hispanic black populations. This book chapter also provides an overview of breast cancer, racial/ethnic disparities in breast cancer, breast cancer incidence and mortality rate linked to hereditary, major risk factors of breast cancer among minority population, breast cancer treatment, and health disparity. A considerable amount of breast cancer treatment research have been conducted, but with limited success for African Americans compared to other ethnic groups. Therefore, new strategies and approaches are needed to promote breast cancer prevention, improve survival rates, reduce breast cancer mortality, and ultimately improve the health outcomes of racial/ethnic minorities. In addition, it is vital that leaders and medical professionals from minority population groups be represented in decision-making in research so that racial disparity in breast cancer can be well-studied, fully addressed, and ultimately eliminated in breast cancer.


Asunto(s)
Neoplasias de la Mama/etnología , Neoplasias de la Mama/epidemiología , Disparidades en el Estado de Salud , Negro o Afroamericano , Femenino , Humanos , Estados Unidos/epidemiología , Población Blanca
13.
Proc Natl Acad Sci U S A ; 113(2): 356-61, 2016 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-26715746

RESUMEN

Vertebrate retinas are generally composed of rod (dim-light) and cone (bright-light) photoreceptors with distinct morphologies that evolved as adaptations to nocturnal/crepuscular and diurnal light environments. Over 70 years ago, the "transmutation" theory was proposed to explain some of the rare exceptions in which a photoreceptor type is missing, suggesting that photoreceptors could evolutionarily transition between cell types. Although studies have shown support for this theory in nocturnal geckos, the origins of all-cone retinas, such as those found in diurnal colubrid snakes, remain a mystery. Here we investigate the evolutionary fate of the rods in a diurnal garter snake and test two competing hypotheses: (i) that the rods, and their corresponding molecular machinery, were lost or (ii) that the rods were evolutionarily modified to resemble, and function, as cones. Using multiple approaches, we find evidence for a functional and unusually blue-shifted rhodopsin that is expressed in small single "cones." Moreover, these cones express rod transducin and have rod ultrastructural features, providing strong support for the hypothesis that they are not true cones, as previously thought, but rather are modified rods. Several intriguing features of garter snake rhodopsin are suggestive of a more cone-like function. We propose that these cone-like rods may have evolved to regain spectral sensitivity and chromatic discrimination as a result of ancestral losses of middle-wavelength cone opsins in early snake evolution. This study illustrates how sensory evolution can be shaped not only by environmental constraints but also by historical contingency in forming new cell types with convergent functionality.


Asunto(s)
Evolución Biológica , Ritmo Circadiano , Colubridae/fisiología , Células Fotorreceptoras Retinianas Conos/citología , Animales , Inmunohistoquímica , Ratones , Modelos Biológicos , Datos de Secuencia Molecular , Células Fotorreceptoras Retinianas Conos/ultraestructura , Pigmentos Retinianos/metabolismo , Células Fotorreceptoras Retinianas Bastones/citología , Células Fotorreceptoras Retinianas Bastones/ultraestructura , Rodopsina/metabolismo , Transducina/metabolismo
14.
Environ Toxicol ; 34(2): 188-202, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30511785

RESUMEN

Human exposure to inorganic arsenic (iAs) is a global health issue. Although there is strong evidence for iAs-induced toxicity at higher levels of exposure, many epidemiological studies evaluating its effects at low exposure levels have reported mixed results. We comprehensively reviewed the literature and evaluated the scientific knowledge on human exposure to arsenic, mechanisms of action, systemic and carcinogenic effects, risk characterization, and regulatory guidelines. We identified areas where additional research is needed. These priority areas include: (1) further development of animal models of iAs carcinogenicity to identify molecular events involved in iAs carcinogenicity; (2) characterization of underlying mechanisms of iAs toxicity; (3) assessment of gender-specific susceptibilities and other factors that modulate arsenic metabolism; (4) sufficiently powered epidemiological studies to ascertain relationship between iAs exposure and reproductive/developmental effects; (5) evaluation of genetic/epigenetic determinants of iAs effects in children; and (6) epidemiological studies of people chronically exposed to low iAs concentrations.


Asunto(s)
Arseniatos/toxicidad , Arsenitos/toxicidad , Investigación Biomédica , Carcinógenos Ambientales/toxicidad , Contaminantes Ambientales/toxicidad , Mutágenos/toxicidad , Animales , Arseniatos/farmacocinética , Arsenitos/farmacocinética , Investigación Biomédica/tendencias , Biotransformación , Carcinógenos Ambientales/farmacocinética , Contaminantes Ambientales/farmacocinética , Humanos , Mutágenos/farmacocinética
15.
Rhinology ; 56(3): 209-215, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29466477

RESUMEN

Mobile health technology is emerging to take a prominent position in the management of chronic diseases. These technologies aim at enhancing patient empowerment via education and self-management. To date, of all the different apps available for patients with sinus disease, none were developed by medical experts dealing with chronic rhinosinusitis (CRS). The European Forum for Research and Education in Allergy and Airway diseases (EUFOREA) has undertaken a multi-stakeholder approach for designing, developing and implementing a tool to support CRS patients in monitoring their symptoms and to provide patients with a digital support platform containing reliable medical information about their disease and treatment options. mySinusitisCoach has been developed by medical experts dealing with CRS in close collaboration with patients, primary care physicians and community pharmacists, meeting the needs of both patients and health care providers. From a research perspective, the generation of real life data will help to validate clinical studies, patient stratification and improve understanding of the socio-economic impact of CRS, thereby paving the way for better treatment strategies.


Asunto(s)
Aplicaciones Móviles , Participación del Paciente , Rinitis/terapia , Autocuidado , Sinusitis/terapia , Enfermedad Crónica , Humanos , Calidad de Vida
16.
Rev Med Liege ; 73(9): 435-438, 2018 Sep.
Artículo en Francés | MEDLINE | ID: mdl-30188027

RESUMEN

The use of gynecological pessary to put back up prolapsed organs to their normal position appears to be as effective as surgical management to relieve symptoms related to uro-genital prolapse and restore body image. This millenary device can be used temporarily, awaiting a surgical solution or as a therapeutic test (mimicking the effect of a surgical procedure to predict its functional outcome or identifying a masked urinary incontinence). It can also represent an alternative to surgery (patient choice, women who wish to complete childbearing or who are unsuitable for surgery because of medical comorbidities) and thus can be used in first intention. Pessary can also be used to confirm or deny the responsibility of pelvic organ prolapse for atypical symptomatology as pelvic heaviness or pain. However, this use requires adjuvant treatment. In this paper, we highlight an original effective process not yet published to optimize the tolerance of pessary.


L'utilisation du pessaire gynécologique afin de réintégrer les organes prolabés dans l'enceinte pelvienne est une alternative efficace dans le soulagement des symptômes liés au prolapsus uro-génital et la restauration tant de l'image corporelle que de l'estime de soi. Ce dispositif millénaire peut être utilisé temporairement, dans l'attente d'une intervention chirurgicale, à titre de test thérapeutique préopératoire (prédiction du résultat fonctionnel attendu, identification d'une possible incontinence urinaire masquée par le prolapsus, confirmation de la responsabilité du trouble de la statique pelvienne quant à une symptomatologie inhabituelle à type de pesanteur pelvienne ou de douleurs). Le pessaire peut aussi être considéré en alternative définitive à la chirurgie (choix de la patiente, désir de grossesse, terrain récusant une intervention). Cette alternative nécessite toutefois un traitement adjuvant. Nous mettons en lumière un procédé original, non encore publié, optimisant la tolérance dudit pessaire.


Asunto(s)
Guías como Asunto , Prolapso de Órgano Pélvico/terapia , Pesarios , Atención Ambulatoria , Femenino , Humanos
17.
Clin Infect Dis ; 65(8): 1356-1358, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29017244

RESUMEN

BACKGROUND: There is no biomarker for diagnosing active tuberculosis in patients with human immunodeficiency virus (HIV) infection. Indoleamine 2, 3-dioxygenase (IDO) is an immunoregulatory enzyme that breaks down tryptophan (Trp) to metabolites known as kynurenines (Kyns). We investigated whether IDO activity, as measured by the ratio of Kyn to Trp, could be used to diagnose or predict active tuberculosis disease in HIV-infected adults. METHODS: Kyn and Trp concentrations were measured using ultraperformance liquid chromatography mass spectrometry in plasma samples from 32 HIV-infected patients in whom active tuberculosis developed and who were followed up prospectively. We compared to 70 HIV-infected control subjects from the same cohort in whom tuberculosis did not develop, matched by age, sex, and CD4 cell count, and 37 unmatched HIV-infected patients with a diagnosis of pneumonia. Clinical parameters, including body mass index, CD4 cell count, HIV load, and C-reactive protein levels were analyzed. RESULTS: At the time of tuberculosis diagnosis, IDO activity was significantly higher in patients with tuberculosis than in controls (P < .001). Six months before tuberculosis diagnosis, IDO activity was significantly higher in all patients who later developed tuberculosis (P < .001) than controls. After 6 months of tuberculosis treatment, IDO activity in patients with tuberculosis declined to levels similar to those in controls. IDO activity was 4-fold higher in patients with tuberculosis than in those with pneumonia, and could be used to distinguish them. With a receiver operating characteristic curve, IDO activity had a sensitivity of 97%, a specificity of 99%, and positive and negative predictive values of 89% and 100% for detecting active tuberculosis disease. CONCLUSION: Plasma IDO activity is suitable as a biomarker of active tuberculosis in HIV-positive patients.


Asunto(s)
Biomarcadores/sangre , Infecciones por VIH/complicaciones , Indolamina-Pirrol 2,3,-Dioxigenasa/sangre , Tuberculosis/sangre , Tuberculosis/complicaciones , Adulto , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tuberculosis/epidemiología
18.
Molecules ; 22(10)2017 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-28937624

RESUMEN

Prostate cancer patients have been suffering from limited treatment options due to late diagnosis, poor drug tolerance, and multi-drug resistance to almost all the current drug treatments. Therefore, it is important to seek a new alternative therapeutic medicine that can effectively prevent the disease and even eradicate the progression and metastasis of prostate cancer. Vernonia amygdalina Delile (VAD) is a common edible vegetable in Cameroon that has been used as a traditional medicine for some human diseases. However, to the best of our knowledge, no previous reports have explored its therapeutic efficacy against human prostate cancer. The objective of the present study was to assess the anticancer activities of VAD methanolic extracts in the prevention and treatment of prostate cancer using human androgen-independent prostate cancer (PC-3) cells as a test model. To achieve our objective, PC-3 cells were treated with various doses of VAD for 48 h. Data generated from the trypan blue test and MTT assay demonstrated that VAD extracts exhibited significant growth-inhibitory effects on PC-3 cells. Collectively, we established for the first time the antiproliferative effects of VAD on PC-3 cells, with an IC50 value of about 196.6 µg/mL. Further experiments, including cell morphology, lipid peroxidation and comet assays, and apoptosis analysis showed that VAD caused growth-inhibitory effects on PC-3 cells through the induction of cell growth arrest, DNA damage, apoptosis, and necrosis in vitro and may provide protection from oxidative stress diseases as a result of its high antioxidant content. These results provide useful data on the anticancer activities of VAD for prostate cancer and demonstrate the novel possibilities of this medicinal plant for developing prostate cancer therapies.


Asunto(s)
Extractos Vegetales/química , Extractos Vegetales/farmacología , Neoplasias de la Próstata/metabolismo , Vernonia/química , Antioxidantes/química , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Humanos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Medicina Tradicional , Estrés Oxidativo/efectos de los fármacos , Hojas de la Planta/química
19.
J Neurosci ; 35(44): 14842-60, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26538654

RESUMEN

Tau accumulation remains one of the closest correlates of neuronal loss in Alzheimer's disease. In addition, tau associates with several other neurodegenerative diseases, collectively known as tauopathies, in which clinical phenotypes manifest as cognitive impairment, behavioral disturbances, and motor impairment. Polyamines act as bivalent regulators of cellular function and are involved in numerous biological processes. The regulation of the polyamines system can become dysfunctional during disease states. Arginase 1 (Arg1) and nitric oxide synthases compete for l-arginine to produce either polyamines or nitric oxide, respectively. Herein, we show that overexpression of Arg1 using adeno-associated virus (AAV) in the CNS of rTg4510 tau transgenic mice significantly reduced phospho-tau species and tangle pathology. Sustained Arg1 overexpression decreased several kinases capable of phosphorylating tau, decreased inflammation, and modulated changes in the mammalian target of rapamycin and related proteins, suggesting activation of autophagy. Arg1 overexpression also mitigated hippocampal atrophy in tau transgenic mice. Conversely, conditional deletion of Arg1 in myeloid cells resulted in increased tau accumulation relative to Arg1-sufficient mice after transduction with a recombinant AAV-tau construct. These data suggest that Arg1 and the polyamine pathway may offer novel therapeutic targets for tauopathies.


Asunto(s)
Arginasa/biosíntesis , Modelos Animales de Enfermedad , Regulación Enzimológica de la Expresión Génica , Tauopatías/enzimología , Tauopatías/patología , Proteínas tau/metabolismo , Animales , Arginasa/genética , Células HeLa , Hipocampo/enzimología , Hipocampo/patología , Humanos , Ratones , Ratones Transgénicos , Tauopatías/genética , Proteínas tau/genética
20.
Clin Exp Allergy ; 46(4): 543-54, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26542195

RESUMEN

BACKGROUND: The fractional exhaled nitric oxide (FENO) and the blood eosinophil count (B-eos) are markers of eosinophilic inflammation used in the diagnosis and management of asthma. The relationships between smoking cigarette and both FENO and B-eos are complex and raise questions about the association between these markers and asthma in smokers. OBJECTIVE: To determine the relationships between both FENO and B-eos on one hand and asthma and atopy on the other, according to smoking status. METHODS: FENO and B-eos were measured in, respectively, 1579 and 1496 of the 1607 middle-aged adults randomly selected from the general population in the cross-sectional ELISABET survey. Allergic asthma was defined as asthma (a self-report of physician-diagnosed asthma, and wheezing in the previous 12 months or the use of asthma medications) with atopy (allergic rhinitis or hayfever in the previous 12 months, or a previous positive prick test or allergen desensitization therapy). Non-allergic asthma was defined as asthma without atopy. RESULTS: The analysis included 812 (51.4%) never, 473 (30%) former and 294 (18.6%) current smokers. A total of 490 (32%) participants were atopic, 80 (5.1%) had allergic asthma, and 31 (2%) had non-allergic asthma. Only 16.2% (18/111) of asthmatics were treated with glucocorticoid inhalants, suggesting that among them a majority of participants had mild asthma. A positive interaction between smoking status and allergic asthma was observed in multivariate models explaining FENO (P = 0.003) and B-eos (P = 0.001). Thus, compared to those without allergic asthma, participants with allergic asthma had higher FENO values (+ 63.4%, 95% CI = [39; 92]) and higher B-eos (+ 63.2% [38.2; 92.7]) in never and former smokers, but not in current smokers. Lastly, an analysis of receiver-operating characteristic curves showed that each of the two markers was able to discriminate moderately allergic asthma but only in non-smokers. CONCLUSIONS & CLINICAL RELEVANCE: FENO and B-eos were associated with the presence of mild allergic asthma only in non-smokers, not in current smokers. These findings raise questions about the clinical value of FENO and B-eos in smokers.


Asunto(s)
Asma/sangre , Asma/metabolismo , Eosinófilos , Espiración , Recuento de Leucocitos , Óxido Nítrico/biosíntesis , Adulto , Asma/diagnóstico , Asma/epidemiología , Biomarcadores , Pruebas Respiratorias , Eosinófilos/inmunología , Eosinófilos/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Factores de Riesgo , Índice de Severidad de la Enfermedad , Fumar/efectos adversos
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