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1.
Oecologia ; 202(2): 239-250, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37253787

RESUMEN

The general assumption that the survival patterns of tropical and southern temperate birds are similar lacks empirical data from higher latitudes. Regional comparisons of New World species are rare, and this assumption has been based on data from African studies. Here, we estimate the survival rates of 88 tropical and southern temperate bird populations (69 species) from eight localities in South America to evaluate the hypothesis that the survival of these populations is homogeneous at the regional scale. We estimated survival based on the Cormack-Jolly-Seber model and compared values from different environments. The survival estimates ranged from 0.30 to 0.80 (0.56 ± 0.12). Apparent survival did not differ significantly between low-latitude tropical environments (03°S) and the other sites from high-latitudes (between 22° and 34°S). Despite a predicted positive trend, body size was not significantly related to survival among passerines. On the other hand, phylogenetic relationships explained more than a third of the variation in bird survival. Based on the largest available database on South American bird species, our findings support the hypothesis that bird survival is homogeneous, at the regional scale, along the southern hemisphere. In particular, we reinforce the hypothesis that climatic variation has a limited influence on bird survival in the southern hemisphere.


Asunto(s)
Clima Tropical , Filogenia , América del Sur , Tamaño Corporal
2.
Chemotherapy ; 68(4): 228-232, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37231886

RESUMEN

Neisseria meningitidis represents an uncommon pathogen of acute bacterial conjunctivitis. In this brief report, we describe a case of meningococcal conjunctivitis in an immunocompetent adult male, with a review of the literature. The patient went to the outpatient ophthalmology clinic complaining of severe ocular discomfort, burning, and redness for more than 2 weeks and, at slit lamp examination, he was diagnosed with a mild conjunctivitis. Microbiology cultures of ocular swabs revealed the growth of colonies, as pure culture, identified as N. meningitidis of serogroup B. A diagnosis of primary meningococcal conjunctivitis was made and treatment of patient with intramuscular injections of ceftriaxone in addition to topical moxifloxacin eye drops for 2 weeks led to clinical improvement and, finally, to a complete recovery, in accordance with microbiological findings. Ophthalmologists must be aware of the possibility of primary meningococcal conjunctivitis cases, even uncommon, and the need to treat with systemic antibiotics and their close contacts with adequate antibiotic chemoprophylaxis.


Asunto(s)
Conjuntivitis Bacteriana , Conjuntivitis , Infecciones Meningocócicas , Neisseria meningitidis , Adulto , Masculino , Humanos , Persona de Mediana Edad , Infecciones Meningocócicas/diagnóstico , Infecciones Meningocócicas/tratamiento farmacológico , Infecciones Meningocócicas/microbiología , Conjuntivitis Bacteriana/diagnóstico , Conjuntivitis Bacteriana/tratamiento farmacológico , Conjuntivitis Bacteriana/microbiología , Antibacterianos/uso terapéutico , Conjuntivitis/diagnóstico , Conjuntivitis/tratamiento farmacológico , Conjuntivitis/microbiología
3.
Nanomedicine ; 40: 102505, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34902550

RESUMEN

A systematic review and meta-analysis were conducted about photodynamic therapy (PDT) associated with nanomedicine approaches in the treatment of human squamous cell carcinoma (HSSC). Independent reviewers conducted all steps in the systematic review. For evaluating the risk of bias, RoB 2, OHAT and SYRCLE tools were used. Meta-analysis was performed using a random-effect model (α = 0.05). For PDT against HSSC, Protoporphyrin IX was the photosensitizer, and liposomes were the nanomaterial more frequently used. Photosensitizers conjugated with nanoparticles exhibited positive results against HSSC. Tumors treated with PDT in combination with a nanotechnology drug-delivery system had an increased capacity for inhibiting the tumor growth rate (51.93%/P < 0.0001) when compared with PDT only. Thus, the PDT associated with nanomedicine approaches against HSCC could be a significant option for use in future clinical studies, particularly due to improved results in tumor growth inhibition.


Asunto(s)
Carcinoma de Células Escamosas , Nanopartículas , Fotoquimioterapia , Carcinoma de Células Escamosas/tratamiento farmacológico , Línea Celular Tumoral , Humanos , Nanomedicina , Nanopartículas/uso terapéutico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico
4.
Parasitol Res ; 121(11): 3203-3215, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36056960

RESUMEN

Espinilho savanna ("seasonal steppe savanna") is a unique vegetation formation of the Pampas biome that is found near the tri-border of Brazil, Uruguay, and Argentina. The Yellow Cardinal (Gubernatrix cristata) is a flagship species of this ecosystem, but it is classified as "critically endangered" in Brazil due to habitat loss and poaching for the illegal trade. Population supplementation through the release of individuals that were captive-bred or apprehended by authorities from the illegal trade has been considered as a conservation strategy for this species; however, the risk of pathogen introduction is a critical concern. We used microscopy and molecular methods to investigate the occurrence of blood parasites in wild passerines (n = 64, including three Yellow Cardinals) at Espinilho State Park, Rio Grande do Sul, Brazil, and in captive Yellow Cardinals (n = 30) at three facilities in Brazil. Haemosporidian parasites were detected in the blood smears of 10.9% of the wild passerines, comprising the morphospecies Haemoproteus erythrogravidus in Rufous-collared Sparrow (Zonotrichia capensis), H. quiscalus in Grayish Baywing (Agelaioides badius), and H. tyranni in Great Kiskadee (Pitangus sulphuratus); these are the southernmost records for these morphospecies and their first record for the Pampas biome. No haemosporidian parasites were detected in the blood smears of the Yellow Cardinals, wild or captive. Microfilariae were detected in the blood smears of 14.1% of the wild passerines, including all wild Yellow Cardinals, and in 43.3% of captive Yellow Cardinals. Trypanosoma sp. was detected in the blood smear of one captive Yellow Cardinal. Nested PCR and gene sequencing of the cyt-b gene of Haemoproteus/Plasmodium was used to test a subset of wild passerines and captive Yellow Cardinals, allowing for the molecular barcoding of H. quiscalus lineage AGEBAD04 and H. tyranni lineage PITSUL01; additionally, DNA identical to that of lineage PITSUL01 was detected in the blood of one captive Yellow Cardinal. This study provides valuable data to support the conservation management of the Yellow Cardinal and other threatened passerines from the Pampas and highlights the need for further studies on the epidemiology and pathology of filarioid worms and trypanosomes in passerines from this biome.


Asunto(s)
Enfermedades de las Aves , Haemosporida , Lepidópteros , Parásitos , Infecciones Protozoarias en Animales , Gorriones , Animales , Enfermedades de las Aves/parasitología , Brasil , Suplementos Dietéticos , Ecosistema , Haemosporida/genética , Parásitos/genética , Filogenia , Infecciones Protozoarias en Animales/epidemiología , Infecciones Protozoarias en Animales/parasitología
5.
Lasers Med Sci ; 37(9): 3443-3450, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35819661

RESUMEN

Photodynamic therapy (PDT) is a therapeutic modality with high contributions in the treatment of cancer. This approach is based on photophysical principles, which presents as a less invasive strategy than conventional therapies. Combined with nanotechnology, the therapy becomes more efficient because nanoparticles (NPs) have advantageous characteristics such as biocompatibility, controlled, and targeted release, promoting solubility and decreasing the toxicity and side effects involved. In this work were developed nanoemulsions containing the methylene blue photosensitizer (MB) (MB/NE) and in the empty form (unloaded/NE). Subsequently, the mentioned nanomaterials were characterized by the measurement of dynamic light scattering (DLS). The MB/NE and unloaded/NE showed appropriate physical and chemical characteristics, with particle size ≤ 200 nm, polydispersity index close to 0.3, and zeta potential exhibiting negative charge, showing stable values during the analysis. The incorporation of the MB did not cause changes in the photophysical profile of the photosensitizer. The quantification performed showed an incorporation rate of 81.9%. Viability studies showed an absence of cytotoxicity for MB/NE in the concentrations of 10-75 µmol·L-1, free MB at the concentration of 75 µmol·L-1, and unloaded NE 47.5% (v/v), presenting viability close to 90%, respectively. PDT in vitro protocols applied to OSCC and HeLa cells showed a decrease in cell viability through only one irradiation, evidencing the photodynamic activity of the formulation when applied to cancer cells. The results obtained were superior to those found in the literature where they use free MB, showing that the association between nanotechnology and PDT optimizes the proposed protocol. From the results obtained, it is possible to indicate that the NE have high stability, with satisfactory physical-chemical parameters, in addition to not presenting cytotoxicity in the tested concentrations, showing their in vitro biocompatibility, in addition to presenting satisfactory effects when combined MB/NE with PDT, showing the potential of MB/NE as a very promising nanostructured photosensitizer for the treatment of some types of cancer.


Asunto(s)
Carcinoma , Fotoquimioterapia , Neoplasias del Cuello Uterino , Femenino , Humanos , Fotoquimioterapia/métodos , Azul de Metileno/farmacología , Azul de Metileno/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Células HeLa
6.
An Acad Bras Cienc ; 93(suppl 3): e20191458, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34550197

RESUMEN

Tawny-bellied Seedeater (Sporophila hypoxantha) is an endangered (in Brazil) grassland dependent species, whose breeding success remains poorly known hampering conservation measures on its breeding grounds. Here we analyze the nest survival of the species in relation to temporal and environmental variables over three breeding seasons in hilly dry grasslands in southern Brazil. The apparent nest success was 40%, and MARK survival 20%. Predation was the main cause of failure, affecting 55% of the unsuccessful nests, followed by desertion, infestation by Philornis fly larvae, cattle trampling and burning. The productivity was 1.77 young per pair. Best models include time-specific factors (nest age and time of breeding season), reflected by a gradual reduction in nest survival over the nesting cycle, accompanied by an increase in temperature, subcutaneous larvae infestation, and predation. Nest site characteristics did not influence nest survival. Predation is more prevalent in the nestling rearing period than during incubation. This tendency may be caused by an increase in the activity in the nests, as is predicted by the Skutch hypothesis. The conclusion that time-specific factors influence nest survival more than ecological variables is important to plan on seasonally dependent conservation and management measures.


Asunto(s)
Comportamiento de Nidificación , Passeriformes , Animales , Bovinos , Ecosistema , Fitomejoramiento , Conducta Predatoria
7.
J Anim Ecol ; 89(2): 423-435, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31571223

RESUMEN

Geographic variation in environmental conditions as well as host traits that promote parasite transmission may impact infection rates and community assembly of vector-transmitted parasites. Identifying the ecological, environmental and historical determinants of parasite distributions and diversity is therefore necessary to understand disease outbreaks under changing environments. Here, we identified the predictors and contributions of infection probability and phylogenetic diversity of Leucocytozoon (an avian blood parasite) at site and species levels across the New World. To explore spatial patterns in infection probability and lineage diversity for Leucocytozoon parasites, we surveyed 69 bird communities from Alaska to Patagonia. Using phylogenetic Bayesian hierarchical models and high-resolution satellite remote-sensing data, we determined the relative influence of climate, landscape, geography and host phylogeny on regional parasite community assembly. Infection rates and parasite diversity exhibited considerable variation across regions in the Americas. In opposition to the latitudinal gradient hypothesis, both the diversity and prevalence of Leucocytozoon parasites decreased towards the equator. Host relatedness and traits known to promote vector exposure neither predicted infection probability nor parasite diversity. Instead, the probability of a bird being infected with Leucocytozoon increased with increasing vegetation cover (NDVI) and moisture levels (NDWI), whereas the diversity of parasite lineages decreased with increasing NDVI. Infection rates and parasite diversity also tended to be higher in cooler regions and higher latitudes. Whereas temperature partially constrains Leucocytozoon diversity and infection rates, landscape features, such as vegetation cover and water body availability, play a significant role in modulating the probability of a bird being infected. This suggests that, for Leucocytozoon, the barriers to host shifting and parasite host range expansion are jointly determined by environmental filtering and landscape, but not by host phylogeny. Our results show that integrating host traits, host ancestry, bioclimatic data and microhabitat characteristics that are important for vector reproduction are imperative to understand and predict infection prevalence and diversity of vector-transmitted parasites. Unlike other vector-transmitted diseases, our results show that Leucocytozoon diversity and prevalence will likely decrease with warming temperatures.


Asunto(s)
Enfermedades de las Aves/epidemiología , Haemosporida/genética , Infecciones , Parásitos , Alaska , Animales , Teorema de Bayes , Aves , Filogenia , Probabilidad
8.
J Exp Zool B Mol Dev Evol ; 332(3-4): 92-98, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31004403

RESUMEN

In vocal learning birds, memorization and song production rely on a set of telencephalic nuclei referred to as the song control system. Seasonal changes in song production are correlated with changes in the volume of the song control nuclei and are influenced by photoperiodic conditions and hormonal cues. The seasonal volume changes in the avian brain that controls singing are thought to involve regulation of neuronal replacement, which is a striking example of neuronal plasticity. The Rufous-bellied Thrush (Turdus rufiventris) is a seasonally breeding bird that actively sings during the spring and summer (breeding season) and is relatively silent in the fall, yet possible mechanisms behind the periodic changes in song production remain unknown. Here, we have examined two song control nuclei: High vocal center (HVC) and robust nucleus of arcopallium (RA) in fall males, spring males, and fall females of Rufous-bellied Thrush. The cytoarchitectonic organization was analyzed and quantified from Nissl-stained sections, and gene expression of song nuclei markers was examined by in situ hybridization during breeding and nonbreeding seasons. We observed a reduction in HVC volume and reductions in parvalbumin, and RGS4 expression in HVC and RA in males during the nonbreeding season. These findings provide evidence of seasonal changes in the song system of a representative tropical-breeding Turdidae species that does not maintain territories or mate bonding, setting the histological and molecular groundwork for future studies aimed at better understanding of song nuclei changes in seasonally breeding songbirds.


Asunto(s)
Encéfalo/anatomía & histología , Estaciones del Año , Pájaros Cantores/fisiología , Vocalización Animal/fisiología , Animales , Encéfalo/fisiología
9.
Mol Ecol ; 28(10): 2681-2693, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30959568

RESUMEN

Identifying the ecological factors that shape parasite distributions remains a central goal in disease ecology. These factors include dispersal capability, environmental filters and geographic distance. Using 520 haemosporidian parasite genetic lineages recovered from 7,534 birds sampled across tropical and temperate South America, we tested (a) the latitudinal diversity gradient hypothesis and (b) the distance-decay relationship (decreasing proportion of shared species between communities with increasing geographic distance) for this host-parasite system. We then inferred the biogeographic processes influencing the diversity and distributions of this cosmopolitan group of parasites across South America. We found support for a latitudinal gradient in diversity for avian haemosporidian parasites, potentially mediated through higher avian host diversity towards the equator. Parasite similarity was correlated with climate similarity, geographic distance and host composition. Local diversification in Amazonian lineages followed by dispersal was the most frequent biogeographic events reconstructed for haemosporidian parasites. Combining macroecological patterns and biogeographic processes, our study reveals that haemosporidian parasites are capable of circumventing geographic barriers and dispersing across biomes, although constrained by environmental filtering. The contemporary diversity and distributions of haemosporidian parasites are mainly driven by historical (speciation) and ecological (dispersal) processes, whereas the parasite community assembly is largely governed by host composition and to a lesser extent by environmental conditions.


Asunto(s)
Aves/parasitología , Ecología , Interacciones Huésped-Parásitos , Malaria Aviar/parasitología , Animales , Haemosporida/genética , Haemosporida/patogenicidad , Especificidad del Huésped , Filogenia , América del Sur
10.
Clin Chem Lab Med ; 57(11): 1680-1689, 2019 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-31348753

RESUMEN

Bloodstream infections (BSIs) remain a potentially life-threatening condition. The gold standard for the diagnosis of BSI is still blood cultures (BCs), and the diagnostic yield depends on clinical and technical factors that have an impact on collection and transportation. Hence, monitoring of the entire pre-analytical process from blood collection to transportation to the microbiology laboratory is critical. To optimize the clinical impact of the diagnostic and therapeutic procedures, a multidisciplinary approach and univocal protocols are mandatory. A board of specialists discussed the available evidence on the pre-analytical process and produced the present document to guide physicians and nurses on the ideal execution of BC: (1) timing and preparation for blood collection; (2) skin antisepsis; (3) blood volume; (4) sampling method and safety; (5) medium to be used; (6) time to BC transportation; and (7) quality assurance and quality management.


Asunto(s)
Cultivo de Sangre/métodos , Recolección de Muestras de Sangre/métodos , Garantía de la Calidad de Atención de Salud/métodos , Adulto , Humanos , Italia
11.
Biofouling ; 35(7): 742-757, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31550929

RESUMEN

The self-produced extracellular polymeric matrix of biofilms renders them difficult to eliminate once they are established. This makes the inhibition of biofilm formation key to successful treatment of biofilm infection. Antimicrobial photodynamic therapy (aPDT) and antimicrobial peptides offer a new approach as antibiofilm strategies. In this study sub-lethal doses of aPDT (with chlorin-e6 (Ce6-PDT) or methylene blue (MB-PDT)) and the peptides AU (aurein 1.2 monomer) or (AU)2K (aurein 1.2 C-terminal dimer) were combined to evaluate their ability to prevent biofilm development by Enterococcus faecalis. Biofilm formation was assessed by resazurin reduction, confocal microscopy, and infrared spectroscopy. All treatments successfully prevented biofilm development. The (AU)2K dimer had a stronger effect, both alone and combined with aPDT, while the monomer AU had significant activity when combined with Ce6-PDT. Additionally, it is shown that the peptides bind to the lipoteichoic acid of the E. faecalis cell wall, pointing to a possible key mechanism of biofilm inhibition.


Asunto(s)
Antibacterianos/química , Biopelículas , Péptidos/química , Fármacos Fotosensibilizantes/química , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Clorofilidas , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/fisiología , Péptidos/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Porfirinas/química
12.
Int J Mol Sci ; 20(16)2019 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-31398812

RESUMEN

Recent scientific research has shown the use of chlorin, phthalocyanines, and porphyrins derivatives as photosensitizers in photodynamic therapy in the treatment of various pathologies, including some of the major skin diseases. Thus, the main goal of this critical review is to catalog the papers that used these photosensitizers in the treatment of acne vulgaris, psoriasis, papillomavirus infections, cutaneous leishmaniasis, and skin rejuvenation, and to explore the photodynamic therapy mechanisms against these conditions alongside their clinical benefits.


Asunto(s)
Indoles/uso terapéutico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/uso terapéutico , Enfermedades de la Piel/tratamiento farmacológico , Piel/efectos de los fármacos , Animales , Humanos , Indoles/farmacología , Isoindoles , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Porfirinas/farmacología , Piel/patología , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/etiología , Resultado del Tratamiento
13.
Int J Mol Sci ; 20(14)2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31340425

RESUMEN

The aim of this study was to perform a systematic review of the literature followed by a meta-analysis about the efficacy of photodynamic therapy (PDT) on the microorganisms responsible for dental caries. The research question and the keywords were constructed according to the PICO strategy. The article search was done in Embase, Lilacs, Scielo, Medline, Scopus, Cochrane Library, Web of Science, Science Direct, and Pubmed databases. Randomized clinical trials and in vitro studies were selected in the review. The study was conducted according the PRISMA guideline for systematic review. A total of 34 articles were included in the qualitative analysis and four articles were divided into two subgroups to perform the meta-analysis. Few studies have achieved an effective microbial reduction in microorganisms associated with the pathogenesis of dental caries. The results highlight that there is no consensus about the study protocols for PDT against cariogenic microorganisms, although the results showed the PDT could be a good alternative for the treatment of dental caries.


Asunto(s)
Infecciones por Bacteroidaceae/tratamiento farmacológico , Candidiasis/tratamiento farmacológico , Caries Dental/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones por Bacteroidaceae/microbiología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Candida/efectos de los fármacos , Candida/crecimiento & desarrollo , Candida/patogenicidad , Candidiasis/microbiología , Curcumina/farmacología , Caries Dental/microbiología , Humanos , Azul de Metileno/farmacología , Porphyromonas gingivalis/efectos de los fármacos , Porphyromonas gingivalis/crecimiento & desarrollo , Porphyromonas gingivalis/patogenicidad , Colorantes de Rosanilina/farmacología , Infecciones Estreptocócicas/microbiología , Streptococcus/efectos de los fármacos , Streptococcus/crecimiento & desarrollo , Streptococcus/patogenicidad , Cloruro de Tolonio/farmacología , Resultado del Tratamiento
14.
Genet Mol Biol ; 43(1 suppl 1): e20190066, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31930277

RESUMEN

Glioblastoma (GBM) is the most common and malignant type of primary brain tumor, showing rapid development and resistance to therapies. On average, patients survive 14.6 months after diagnosis and less than 5% survive five years or more. Several pieces of evidence have suggested that the DNA damage signaling and repair activities are directly correlated with GBM phenotype and exhibit opposite functions in cancer establishment and progression. The functions of these pathways appear to present a dual role in tumorigenesis and cancer progression. Activation and/or overexpression of ATRX, ATM and RAD51 genes were extensively characterized as barriers for GBM initiation, but paradoxically the exacerbated activity of these genes was further associated with cancer progression to more aggressive stages. Excessive amounts of other DNA repair proteins, namely HJURP, EXO1, NEIL3, BRCA2, and BRIP, have also been connected to proliferative competence, resistance and poor prognosis. This scenario suggests that these networks help tumor cells to manage replicative stress and treatment-induced damage, diminishing genome instability and conferring therapy resistance. Finally, in this review we address promising new drugs and therapeutic approaches with potential to improve patient survival. However, despite all technological advances, the prognosis is still dismal and further research is needed to dissect such complex mechanisms.

15.
AAPS PharmSciTech ; 20(7): 253, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31309346

RESUMEN

Drug delivery systems (DDS) can be designed to enrich the pharmacological and therapeutic properties of several drugs. Many of the initial obstacles that impeded the clinical applications of conventional DDS have been overcome with nanotechnology-based DDS, especially those formed by chitosan (CS). CS is a linear polysaccharide obtained by the deacetylation of chitin, which has potential properties such as biocompatibility, hydrophilicity, biodegradability, non-toxicity, high bioavailability, simplicity of modification, aqueous solubility, and excellent chemical resistance. Furthermore, CS can prepare several DDS as films, gels, nanoparticles, and microparticles to improve delivery of drugs, such as photosensitizers (PS). Thus, CS-based DDS are broadly investigated for photodynamic therapy (PDT) of cancer and fungal and bacterial diseases. In PDT, a PS is activated by light of a specific wavelength, which provokes selective damage to the target tissue and its surrounding vasculature, but most PS have low water solubility and cutaneous photosensitivity impairing the clinical use of PDT. Based on this, the application of nanotechnology using chitosan-based DDS in PDT may offer great possibilities in the treatment of diseases. Therefore, this review presents numerous applications of chitosan-based DDS in order to improve the PDT for cancer and fungal and bacterial diseases.


Asunto(s)
Quitosano/química , Sistemas de Liberación de Medicamentos , Fotoquimioterapia , Fármacos Fotosensibilizantes/administración & dosificación , Infecciones Bacterianas/tratamiento farmacológico , Humanos , Micosis/tratamiento farmacológico , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Fármacos Fotosensibilizantes/química , Polisacáridos
16.
AAPS PharmSciTech ; 20(6): 225, 2019 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-31214798

RESUMEN

The vaginal mucosa is a very promising route for drug administration due to its high permeability and the possibility to bypass first pass metabolism; however, current vaginal dosage forms present low retention times due to their dilution in vaginal fluids, which hampers the efficacy of many pharmacological treatments. In order to overcome these problems, this study proposes to develop a mucoadhesive in situ gelling liquid crystalline precursor system composed of 30% of oleic acid and cholesterol (7:1), 40% of ethoxylated and propoxylated cetyl alcohol, and 30% of a dispersion of 16% Poloxamer 407. The effect of the dilution with simulated vaginal fluid (SVF) on this system was evaluated by polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), rheological studies, texture profile analysis (TPA), mucoadhesion study, in vitro drug release test using hypericin (HYP) as drug model, and cytotoxicity assay. PLM and SAXS confirmed the formation of an isotropic system. After the addition of three different concentrations of SVF (30, 50, and 100%), the resultant formulations presented anisotropy and characteristics of viscous lamellar phases. Rheology shows that formulations with SVF behaved as a non-Newtonian fluid with suitable shear thinning for vaginal application. TPA and mucoadhesion assays indicated the formation of long-range ordered systems as the amount of SVF increases which may assist in the fixation of the formulation on the vaginal mucosa. The formulations were able to control about 75% of the released HYP demonstrating a sustained release profile. Finally, all formulations acted as safe vaginal drug delivery systems.


Asunto(s)
Administración Intravaginal , Geles/metabolismo , Membrana Mucosa/metabolismo , Animales , Líquidos Corporales , Cristalización , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Femenino , Poloxámero/metabolismo , Reología , Dispersión del Ángulo Pequeño , Vagina , Viscosidad , Difracción de Rayos X
17.
Molecules ; 23(2)2018 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-29470387

RESUMEN

Chitosan (CH) is a biopolymer that exhibits a number of interesting properties such as anti-inflammatory and antibacterial activity and is also a promising platform for the incorporation of photosensitizing agents. This study aimed to evaluate the efficacy of antimicrobial activity of chitosan hydrogel formulation alone and in combination with the methylene blue (MB) associated with antimicrobial photodynamic therapy (aPDT) against planktonic and biofilm phase of Propionibacterium acnes. Suspensions were sensitized with 12.5, 25.0, 37.5, 50.0 µg/mL of MB for 10 min and biofilms to 75, 100 and 150 µg/mL for 30 min then exposed to red light (660 nm) at 90 J/cm² and 150 J/cm² respectively. After treatments, survival fractions were calculated by counting the number of colony-forming units. The lethal effect of aPDT associated with CH hydrogel in planktonic phase was achieved with 12.5 µg/mL MB and 1.9 log10 biofilm reduction using 75 µg/mL MB. Rheological studies showed that formulations exhibited pseudoplastic non-Newtonian behavior without thixotropy. Bioadhesion test evidenced that the formulations are highly adhesive to skin and the incorporation of MB did not influence the bioadhesive force of the formulations.


Asunto(s)
Antiinfecciosos/química , Quitosano/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Propionibacterium acnes/efectos de los fármacos , Antiinfecciosos/farmacología , Biopelículas/efectos de los fármacos , Quitosano/farmacología , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Azul de Metileno/química , Fotoquimioterapia , Propionibacterium acnes/patogenicidad , Reología
18.
BMC Cancer ; 17(1): 123, 2017 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-28187758

RESUMEN

BACKGROUND: Photodynamic therapy (PDT) has proven to be a promising alternative to current cancer treatments, especially if combined with conventional approaches. The technique is based on the administration of a non-toxic photosensitizing agent to the patient with subsequent localized exposure to a light source of a specific wavelength, resulting in a cytotoxic response to oxidative damage. The present study intended to evaluate in vitro the type of induced death and the genotoxic and mutagenic effects of PDT alone and associated with cisplatin. METHODS: We used the cell lines SiHa (ATCC® HTB35™), C-33 A (ATCC® HTB31™) and HaCaT cells, all available at Dr. Christiane Soares' Lab. Photosensitizers were Photogem (PGPDT) and methylene blue (MBPDT), alone or combined with cisplatin. Cell death was accessed through Hoechst and Propidium iodide staining and caspase-3 activity. Genotoxicity and mutagenicity were accessed via flow cytometry with anti-gama-H2AX and micronuclei assay, respectively. Data were analyzed by one-way ANOVA with Tukey's posthoc test. RESULTS: Both MBPDT and PGPDT induced caspase-independent death, but MBPDT induced the morphology of typical necrosis, while PGPDT induced morphological alterations most similar to apoptosis. Cisplatin predominantly induced apoptosis, and the combined therapy induced variable rates of apoptosis- or necrosis-like phenotypes according to the cell line, but the percentage of dead cells was always higher than with monotherapies. MBPDT, either as monotherapy or in combination with cisplatin, was the unique therapy to induce significant damage to DNA (double strand breaks) in the three cell lines evaluated. However, there was no mutagenic potential observed for the damage induced by MBPDT, since the few cells that survived the treatment have lost their clonogenic capacity. CONCLUSIONS: Our results elicit the potential of combined therapy in diminishing the toxicity of antineoplastic drugs. Ultimately, photodynamic therapy mediated by either methylene blue or Photogem as monotherapy or in combination with cisplatin has low mutagenic potential, which supports its safe use in clinical practice for the treatment of cervical cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Cisplatino/farmacología , Luz , Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Muerte Celular/efectos de la radiación , Línea Celular , Línea Celular Tumoral , Femenino , Histonas/metabolismo , Humanos , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Micronúcleos con Defecto Cromosómico/efectos de la radiación , Fosforilación/efectos de los fármacos , Fosforilación/efectos de la radiación , Fotoquimioterapia/métodos , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología
19.
Mycoses ; 59(9): 594-601, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27061932

RESUMEN

Invasive fungal infections, usually Aspergillus and Candida, represent a major cause of morbidity and mortality in patients with malignant haematological diseases, but in the last years rare fungal infections have more frequently been reported. Here, we report the clinical history of three patients affected with haematological malignancies who developed an infection caused by Geotrichum (G.) clavatum. Two out of three patients were affected by acute myeloid leukaemia (AML), and one by mantle cell lymphoma (MCL). All patients received cytarabine-based chemotherapeutic regimens and developed G. clavatum infection within 3 weeks from therapy initiation. In all cases, G. clavatum was isolated from central venous catheter and peripheral blood cultures. In vitro susceptibility test confirmed an intrinsic resistance to echinocandins and, in all cases, visceral localisations (spleen, liver and lung) were documented by total body computed tomography (CT) scan. A prolonged antifungal therapy with high doses liposomal amphotericin-B was necessary to obtain fever resolution. Only the patient with MCL died while the other two AML recovered, and one of them after received an allogeneic stem cell transplantation. We consecutively reviewed all published cases of infection caused by G. clavatum. Our experience and literature review indicate that G. clavatum can cause invasive infection in haematological patients, mainly in those with acute leukaemia.


Asunto(s)
Geotricosis/complicaciones , Neoplasias Hematológicas/complicaciones , Infecciones Fúngicas Invasoras/complicaciones , Adulto , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Catéteres Venosos Centrales/microbiología , Farmacorresistencia Fúngica , Equinocandinas/uso terapéutico , Resultado Fatal , Femenino , Geotricosis/sangre , Geotricosis/epidemiología , Geotricosis/microbiología , Geotrichum/efectos de los fármacos , Neoplasias Hematológicas/epidemiología , Trasplante de Células Madre Hematopoyéticas , Humanos , Infecciones Fúngicas Invasoras/diagnóstico por imagen , Infecciones Fúngicas Invasoras/epidemiología , Infecciones Fúngicas Invasoras/microbiología , Italia , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/microbiología , Hígado/diagnóstico por imagen , Hígado/microbiología , Pulmón/diagnóstico por imagen , Pulmón/microbiología , Linfoma de Células del Manto/complicaciones , Linfoma de Células del Manto/tratamiento farmacológico , Linfoma de Células del Manto/microbiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Bazo/diagnóstico por imagen , Bazo/microbiología , Tomografía Computarizada por Rayos X , Adulto Joven
20.
Int J Mol Sci ; 17(5)2016 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-27213356

RESUMEN

Antimicrobial photodynamic therapy (aPDT) is increasingly being explored for treatment of periodontitis. Here, we investigated the effect of aPDT on human dental plaque bacteria in suspensions and biofilms in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles (MB-NP) and red light at 660 nm. The effect of MB-NP-based aPDT was also evaluated in a clinical pilot study with 10 adult human subjects with chronic periodontitis. Dental plaque samples from human subjects were exposed to aPDT-in planktonic and biofilm phases-with MB or MB-NP (25 µg/mL) at 20 J/cm² in vitro. Patients were treated either with ultrasonic scaling and scaling and root planing (US + SRP) or ultrasonic scaling + SRP + aPDT with MB-NP (25 µg/mL and 20 J/cm²) in a split-mouth design. In biofilms, MB-NP eliminated approximately 25% more bacteria than free MB. The clinical study demonstrated the safety of aPDT. Both groups showed similar improvements of clinical parameters one month following treatments. However, at three months ultrasonic SRP + aPDT showed a greater effect (28.82%) on gingival bleeding index (GBI) compared to ultrasonic SRP. The utilization of PLGA nanoparticles encapsulated with MB may be a promising adjunct in antimicrobial periodontal treatment.


Asunto(s)
Biopelículas/efectos de los fármacos , Ácido Láctico/administración & dosificación , Azul de Metileno/administración & dosificación , Nanopartículas , Periodontitis/tratamiento farmacológico , Periodontitis/microbiología , Fotoquimioterapia/métodos , Ácido Poliglicólico/administración & dosificación , Adulto , Anciano , Femenino , Humanos , Ácido Láctico/química , Masculino , Azul de Metileno/química , Persona de Mediana Edad , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
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