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1.
J Am Chem Soc ; 145(8): 4534-4544, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36780327

RESUMO

Here, we report six novel, easily accessible BODIPY-based agents for cancer treatment. In contrast to established photodynamic therapy (PDT) agents, these BODIPY-based compounds show additional photothermal activity and their cytotoxicity is not dependent on the generation of reactive oxygen species (ROS). The agents show high photocytotoxicity upon irradiation with light and low dark toxicity in different cancer cell lines in 2D culture as well as in 3D multicellular tumor spheroids (MCTSs). The ratio of dark to light toxicity (phototoxic index, PI) of these agents reaches striking values exceeding 830,000 after irradiation with energetically low doses of light at 630 nm. The oxygen-dependent mechanism of action (MOA) of established photosensitizers (PSs) hampers effective clinical deployment of these agents. Under hypoxic conditions (0.2% O2), which are known to limit the efficiency of conventional PSs in solid tumors, photocytotoxicity was induced at the same concentration levels, indicating an oxygen-independent photothermal MOA. With a PI exceeding 360,000 under hypoxic conditions, both PI values are the highest reported to date. We anticipate that small molecule agents with a photothermal MOA, such as the BODIPY-based compounds reported in this work, may overcome this barrier and provide a new avenue to cancer therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Compostos de Boro/farmacologia , Compostos de Boro/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Oxigênio
2.
Planta Med ; 87(14): 1206-1218, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34528222

RESUMO

Efficient wound treatment that addresses associated infections and inflammation remains one of the big unmet needs, especially in low- and middle-income countries. One strategy for securing better healthcare can be using medicinal plants if sufficient evidence on their safety and therapeutic benefits can be ascertained. A unique novel opportunity could be photo-enhanced wound treatment with a combination of light-sensitive plant preparations and local exposure to daylight. Data mining strategies using existing resources offer an excellent basis for developing such an approach with many potential plant candidates. In the present analysis, we researched the 535 botanical drugs included in the Chinese pharmacopeia and identified 183 medicinal plant species, 82 for treating open wounds caused by trauma and 101 for inflammatory skin conditions. After further screening for reports on the presence of known photoactive compounds, we determined a core group of 10 scientifically lesser-known botanical species that may potentially be developed into more widely used topical preparations for photodynamic treatment of infected wounds. Our predictive approach may contribute to developing a more evidence-based use of herbal medicines.


Assuntos
Plantas Medicinais , China , Mineração de Dados , Medicina Tradicional , Preparações de Plantas
3.
Radiographics ; 38(7): 2195-2211, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30422765

RESUMO

The uterus, which plays an important role in the reproductive process, provides a home for the developing fetus and so must be in a stable, though flexible, location. Various structures with suspensory ligaments help provide this berth. MRI with high spatial resolution allows us to detect and evaluate these relatively fine structures. Under physiologic conditions, MRI can be used to depict uterine and ovarian ligaments (ie, the uterosacral, cardinal, and round ligaments, as well as the suspensory ligament of the ovary). In the presence of pathologic conditions (inflammation, endometriosis, tumors), the suspensory ligaments may appear thickened or invaded, which makes their delineation easier. Understanding the normal anatomy of the suspensory ligaments of the female genital organs and using a standardized nomenclature are essential for identifying and reporting related pathologic conditions. The female pelvic anatomy and the suspensory ligaments of the female genital organs are described as depicted with MRI. Also, the compartmental anatomy of the female pelvis is explained, including the extraperitoneal pelvic spaces. Finally, a checklist is provided for structured reporting of the MRI findings in the female pelvis. Online supplemental material is available for this article. ©RSNA, 2018.


Assuntos
Doenças dos Genitais Femininos/diagnóstico por imagem , Doenças dos Genitais Femininos/patologia , Genitália Feminina/anatomia & histologia , Genitália Feminina/diagnóstico por imagem , Ligamentos/anatomia & histologia , Ligamentos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Feminino , Humanos
4.
J Nanobiotechnology ; 14(1): 68, 2016 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-27604187

RESUMO

BACKGROUND: Photosensitizers are used in photodynamic therapy (PDT) to destruct tumor cells, however, their limited solubility and specificity hampers routine use, which may be overcome by encapsulation. Several promising novel nanoparticulate drug carriers including liposomes, polymeric nanoparticles, metallic nanoparticles and lipid nanocomposites have been developed. However, many of them contain components that would not meet safety standards of regulatory bodies and due to difficulties of the manufacturing processes, reproducibility and scale up procedures these drugs may eventually not reach the clinics. Recently, we have designed a novel lipid nanostructured carrier, namely Lipidots, consisting of nontoxic and FDA approved ingredients as promising vehicle for the approved photosensitizer m-tetrahydroxyphenylchlorin (mTHPC). RESULTS: In this study we tested Lipidots of two different sizes (50 and 120 nm) and assessed their photodynamic potential in 3-dimensional multicellular cancer spheroids. Microscopically, the intracellular accumulation kinetics of mTHPC were retarded after encapsulation. However, after activation mTHPC entrapped into 50 nm particles destroyed cancer spheroids as efficiently as the free drug. Cell death and gene expression studies provide evidence that encapsulation may lead to different cell killing modes in PDT. CONCLUSIONS: Since ATP viability assays showed that the carriers were nontoxic and that encapsulation reduced dark toxicity of mTHPC we conclude that our 50 nm photosensitizer carriers may be beneficial for clinical PDT applications.


Assuntos
Mesoporfirinas/farmacologia , Fotoquimioterapia/métodos , Esferoides Celulares/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Portadores de Fármacos/administração & dosagem , Emulsões/farmacologia , Humanos , Lipídeos/química , Teste de Materiais , Mesoporfirinas/administração & dosagem , Nanopartículas/química , Tamanho da Partícula , Esferoides Celulares/efeitos da radiação , Células Tumorais Cultivadas
5.
J Nanobiotechnology ; 14(1): 71, 2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27716314

RESUMO

BACKGROUND: Photodynamic therapy (PDT) as promising alternative to conventional cancer treatments works by irradiation of a photosensitizer (PS) with light, which creates reactive oxygen species and singlet oxygen (1O2), that damage the tumor. However, a routine use is hindered by the PS's poor water solubility and extended cutaneous photosensitivity of patients after treatment. In our study we sought to overcome these limitations by encapsulation of the PS m-tetrahydroxyphenylchlorin (mTHPC) into a biocompatible nanoemulsion (Lipidots). RESULTS: In CAL-33 tumor bearing nude mice we compared the Lipidots to the existing liposomal mTHPC nanoformulation Foslip and the approved mTHPC formulation Foscan. We established biodistribution profiles via fluorescence measurements in vivo and high performance liquid chromatography (HPLC) analysis. All formulations accumulated in the tumors and we could determine the optimum treatment time point for each substance (8 h for mTHPC, 24 h for Foslip and 72 h for the Lipidots). We used two different light doses (10  and 20 J/cm2) and evaluated immediate PDT effects 48 h after treatment and long term effects 14 days later. We also analyzed tumors by histological analysis and performing reverse transcription real-time PCR with RNA extracts. Concerning tumor destruction Foslip was superior to Lipidots and Foscan while with regard to tolerance and side effects Lipidots were giving the best results. CONCLUSIONS: We could demonstrate in our study that nanoformulations are superior to the free PS mTHPC. The development of a potent nanoformulation is of major importance because the free PS is related to several issues such as poor bioavailability, solubility and increased photosensibility of patients. We could show in this study that Foslip is very potent in destroying the tumors itself. However, because the Lipidots' biocompatibility is outstanding and superior to the liposomes we plan to carry out further investigations and protocol optimization. Both nanoformulations show great potential to revolutionize PDT in the future.


Assuntos
Emulsões/uso terapêutico , Lipossomos/uso terapêutico , Nanoestruturas/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Emulsões/farmacologia , Feminino , Lipossomos/química , Lipossomos/farmacologia , Camundongos , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Fármacos Fotossensibilizantes/farmacologia
6.
Int Urogynecol J ; 26(5): 685-91, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25421935

RESUMO

INTRODUCTION AND HYPOTHESIS: Multiphoton microscopy (MPM) is a nonlinear, high-resolution laser scanning technique and a powerful approach for analyzing the spatial architecture within tissues. To demonstrate the potential of this technique for studying the extracellular matrix of the pelvic organs, we aimed to establish protocols for the detection of collagen and elastin in the vagina and to compare the MPM density of these fibers to fibers detected using standard histological methods. METHODS: Samples of the anterior vaginal wall were obtained from nine patients undergoing a hysterectomy or cystocele repair. Samples were shock frozen, fixed with formaldehyde or Thiel's solution, or left untreated. Samples were imaged with MPM to quantify the amount of collagen and elastin via second harmonic generation and autofluorescence, respectively. In six patients, sample sections were also histologically stained and imaged with brightfield microscopy. The density of the fibers was quantified using the StereoInvestigator and Cavalieri software. RESULTS: With MPM, collagen and elastin could be visualized to a depth of 100 µm, and no overlap of signals was detected. The different tissue processing protocols used did not result in significantly different fiber counts after MPM. MPM-based fiber quantifications are comparable to those based on conventional histological stains. However, MPM provided superior resolution, particularly of collagen fibers. CONCLUSIONS: MPM is a robust, rapid, and label-free method that can be used to quantify the collagen and elastin content in thick specimens of the vagina. It is an excellent tool for future three-dimensional studies of the extracellular matrix in patients with pelvic organ prolapse.


Assuntos
Colágeno , Tecido Conjuntivo/anatomia & histologia , Elastina , Microscopia Confocal/métodos , Vagina/anatomia & histologia , Matriz Extracelular , Feminino , Técnicas Histológicas , Humanos , Imageamento Tridimensional , Microscopia de Fluorescência por Excitação Multifotônica
7.
Biomacromolecules ; 14(4): 1010-7, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23470196

RESUMO

As functionalized chitosans hold great potential for the development of effective and broad-spectrum antibiotics, representative chitosan derivatives were tested for antimicrobial activity in neutral media: trimethyl chitosan (TMC), carboxy-methyl chitosan (CMC), and chitosan-thioglycolic acid (TGA; medium molecular weight: MMW-TGA; low molecular weight: LMW-TGA). Colony forming assays indicated that LMW-TGA displayed superior antimicrobial activity over the other derivatives tested: a 30 min incubation killed 100% Streptococcus sobrinus (Gram-positive bacteria) and reduced colony counts by 99.99% in Neisseria subflava (Gram-negative bacteria) and 99.97% in Candida albicans (fungi). To elucidate LMW-TGA effects at the cellular level, microscopic studies were performed. Use of fluorescein isothiocyanate (FITC)-labeled chitosan derivates in confocal microscopy showed that LMW-TGA attaches to microbial cell walls, while transmission electron microscopy indicated that this derivative severely affects cell wall integrity and intracellular ultrastructure in all species tested. We therefore propose LMW-TGA as a promising and effective broad-band antimicrobial compound.


Assuntos
Candida albicans/efeitos dos fármacos , Quitosana/farmacologia , Neisseria/efeitos dos fármacos , Streptococcus sobrinus/efeitos dos fármacos , Tioglicolatos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Parede Celular/efeitos dos fármacos , Quitosana/análogos & derivados , Quitosana/química , Testes de Sensibilidade Microbiana , Tioglicolatos/química
8.
Plants (Basel) ; 12(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36679060

RESUMO

Harmful usage of tobacco is a global public health problem associated with adverse health effects and addiction. Yet, in the Peruvian Amazon, the native region of Nicotiana rustica L., this plant is used in remarkably different manners: it is considered a potent medicinal plant, applied in liquid form for oral ingestion to treat mental health problems, a common and ancient healing practice in this region. Using a transdisciplinary field research approach with mixed ethnopsychological methods, this work aimed to report for the first time a case study in this context. The intervention took place in the Peruvian Amazon (Loreto) and involved ritual tobacco ingestion in a weeklong retreat-like frame, administered by a specialized traditional Amazonian healer. The patient was a 37-year-old woman with diagnosed mood, anxiety, and attention deficit disorders, as well as a chronic somatic condition. We applied qualitative experience-sampling during and quantitative symptom assessments pre- and post-treatment. Our findings offer a detailed description of the experiential therapeutic process during the treatment week and suggest clinically relevant improvements in patient well-being. This work is significant in view of the globally prevalent harmful uses of tobacco and the current scientific trend of revisiting herbal psychoactives (e.g., cannabis, psilocybin) for their therapeutic potentials.

9.
J Ethnopharmacol ; 286: 114910, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34933085

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Indigenous groups of the Amazon have developed intricate methods for the application of psychoactives, among which particularly the dieta or diet method of Peruvian-Amazonian traditional medicine stands out. It is a retreat-like intervention involving lengthy periods of social, behavioural, and alimentary restrictions, while ingesting specially prepared plant substances. The interplay of the dietary conditions and plants ingested sensitizes the dieter to receive healing, strength, guidance, and knowledge. From a clinical scientific point of view, the method has remained largely underexplored, but seems more pertinent than ever given the increasing interest in Amazonian psychoactive preparations including ayahuasca (Banisteriopsis caapi) and the burgeoning field of psychedelic-assisted therapies in general. AIM OF THE STUDY: This study offers a descriptive account and emic interpretation of the Peruvian-Amazonian dieta. More specifically we document in detail the procedure, its context and purpose of application, effects, modes of action, adverse effects, and risks, from the perspectives of a sample of Peruvian traditional healers. The Peruvian-Amazonian dieta is a multi-purpose method for making use of medicinal plants, many of which (but not all), are psychoactive; the current work especially focuses on its therapeutic applications in conjunction with psychoactives. METHODS: We interviewed 16 healers working in the Ucayali, San Martín, and Loreto provinces of Peru using a semi-structured interview approach. Interviews were audio-recorded and transcribed verbatim. The extensive data derived from these interviews were analysed by means of computer-assisted manifest qualitative content analysis using a theory-advancing approach. Over 500 coded text segments were categorized, resulting in 7 main theme clusters and corresponding sub-themes. RESULTS: The interviewed healers described a complex intervention with multifaceted applications (treatment, prevention, training) and effects in various domains (body, mind, spirit, energy). The process was portrayed as transformative, with benefits attributed to the effects of the so-called teacher plants in conjunction with the diet's conditions, along with the skill of the healer guiding the intervention. Further, a detailed risk assessment revealed sophisticated safety measures and tools designed to address adverse responses. The importance of adequate training of the healer that administers the diet was particularly highlighted in this context. CONCLUSIONS: The dieta is a central therapeutic concept and tool in Peruvian-Amazonian traditional medicine and a unique method for using psychoactive plants. Multidisciplinary health research that includes traditional treatment methods from Indigenous cultures, Amazonian and other, should not be neglected in the current global interest in psychedelic therapies; such research may in the long-term contribute to a more inclusive psychedelic research paradigm as well as healthcare practice in countries where rich traditional healing systems exist, and perhaps beyond. It may also contribute to the recognition of the Indigenous healers as not only historical forerunners, but also current leading experts in psychedelic medicine.


Assuntos
Dieta , Medicina Tradicional/métodos , Preparações de Plantas/administração & dosagem , Plantas Medicinais/química , Banisteriopsis/química , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevistas como Assunto , Peru , Preparações de Plantas/efeitos adversos , Psicotrópicos/administração & dosagem , Psicotrópicos/efeitos adversos , Medição de Risco/métodos
10.
Cancers (Basel) ; 14(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36230544

RESUMO

In this paper, we describe the development and evaluation of a novel tissue-holding device (THD) for use during robotic-assisted laparoscopic partial nephrectomy. The THD is a vacuum-based apparatus made of either 3D-printed polyethylene or stainless steel. The proximal end connects to suction tubing routed outside the body, while the distal end is conically shaped and designed to firmly interface with the tumor. Device feasibility studies were performed on six porcine kidneys, two porcine livers, and two embalmed human cadavers. A Likert-scale rating was used to assess device setup, suction, and tissue handling. Additional tests were performed using the daVinci Xi® robotic system. Finally, the holding force of the THD was assessed using different standard vacuum systems and pressure settings. In porcine tissue, the device setup, tissue suction, and handling were rated as "good". THD insertion and removal was uncomplicated. In a simulated transabdominal approach on fixed human cadavers, the device setup, suction, and tissue handling were also rated as "good". No macroscopic tissue compromise or device deterioration was noted. The handling and holding abilities using the daVinci Xi® robotic system were also rated "good". The device was able to successfully hold over 300 g of tissue at a suction pressure of -600 mmHg. The preliminary evaluation of the THD demonstrated satisfactory results.

11.
Small ; 7(19): 2808-14, 2011 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-21953786

RESUMO

Polyoxometalate/carboxymethyl chitosan nanocomposites with an average diameter of 130 nm are synthesized and labeled with fluorescein isothiocyanate (FITC) for a combined drug-carrier and cellular-monitoring approach. [Eu(ß(2) -SiW(11) O(39) )(2) ](13-) /CMC nanospheres as a representative example do not display cytotoxicity for POM concentrations up to 2 mg mL(-1) . Cellular uptake of fluoresecently labelled {EuSiW(11) O(39) }/FITC-CMC nanoparticles is monitored with confocal laser scanning microscopy. Nanoparticle uptake occurs after incubation times of around 1 h and no cyctotoxic effects are observed upon prolonged treatment. The preferential location of the POM/CMC nanocomposites in the perinuclear region is furthermore verified with transmission electron microscopy investigations on unlabeled nanoparticles. Therefore, this approach is a promising dual strategy for the safe cellular transfer and monitoring of bioactive POMs.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanocompostos/química , Compostos de Tungstênio/farmacologia , Morte Celular/efeitos dos fármacos , Quitosana/análogos & derivados , Quitosana/química , Células HeLa , Humanos , Microscopia Confocal , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier
12.
J Nanobiotechnology ; 9: 32, 2011 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-21834958

RESUMO

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is currently the eighth leading cause of cancer death worldwide. The often severe side effects, functional impairments and unfavorable cosmetic outcome of conventional therapies for HNSCC have prompted the quest for novel treatment strategies, including the evaluation of nanotechnology to improve e.g. drug delivery and cancer imaging. Although silica nanoparticles hold great promise for biomedical applications, they have not yet been investigated in the context of HNSCC. In the present in-vitro study we thus analyzed the cytotoxicity, uptake and intracellular fate of 200-300 nm core-shell silica nanoparticles encapsulating fluorescent dye tris(bipyridine)ruthenium(II) dichloride with hydroxyl-, aminopropyl- or PEGylated surface modifications (Ru@SiO2-OH, Ru@SiO2-NH2, Ru@SiO2-PEG) in the human HNSCC cell line UMB-SCC 745. RESULTS: We found that at concentrations of 0.125 mg/ml, none of the nanoparticles used had a statistically significant effect on proliferation rates of UMB-SCC 745. Confocal and transmission electron microscopy showed an intracellular appearance of Ru@SiO2-OH and Ru@SiO2-NH2 within 30 min. They were internalized both as single nanoparticles (presumably via clathrin-coated pits) or in clusters and always localized to cytoplasmic membrane-bounded vesicles. Immunocytochemical co-localization studies indicated that only a fraction of these nanoparticles were transferred to early endosomes, while the majority accumulated in large organelles. Ru@SiO2-OH and Ru@SiO2-NH2 nanoparticles had never been observed to traffic to the lysosomal compartment and were rather propagated at cell division. Intracellular persistence of Ru@SiO2-OH and Ru@SiO2-NH2 was thus traceable over 5 cell passages, but did not result in apparent changes in cell morphology and vitality. In contrast to Ru@SiO2-OH and Ru@SiO2-NH2 uptake of Ru@SiO2-PEG was minimal even after 24 h. CONCLUSIONS: Our study is the first to provide evidence that silica-based nanoparticles may serve as useful tools for the development of novel treatment options in HNSCC. Their long intracellular persistence could be of advantage for e.g. chronic therapeutic modalities. However, their complex endocytotic pathways require further investigations.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Nanopartículas , Dióxido de Silício/farmacologia , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/farmacologia , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação , Corantes Fluorescentes/farmacologia , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Propriedades de Superfície
13.
J Pharm Pharmacol ; 73(7): 956-967, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33886964

RESUMO

BACKGROUND AND OBJECTIVES: Adequate treatment of wounds remains one of the major medical needs globally, most notably in the regions with poor or limited access to health care. In many local and traditional systems of medicine, plants are often widely used for treating infected wounds. AIM AND OBJECTIVES: The overarching aim of this project was selection of potential species for use in a future treatment by combining with plant resources with aspects of antimicrobial photodynamic therapy (aPDT). Specifically, we focussed on species used locally in the Himalayan region for the treatment of skin disorders and then assessed the existing pharmacological evidence for key species based on the published evidence available. METHODS: Database searches were performed to identify relevant publications describing local and traditional uses of plants in the Himalayan region of Bhutan, PR China, India, Nepal and Pakistan. Using the Global Biodiversity Information Facility (GBIF), species were researched in terms of their distribution including in different climatic regions, focussing on species mostly found in higher climatic zones (based on the Köppen-Geiger climate classification). For species used in three or more countries and restricted to the higher altitudes, data on safety, pharmacology, as it relates to dermatological conditions, and phytochemistry were retrieved. KEY FINDINGS: The study identified a total of 606 species that are used in the treatment of various skin conditions often associated with infections reported in 84 articles. Common weeds like Ageratum conyzoides and Bidens pilosa, widely used and cultivated species like Centealla asiatiaca and Prunus armenica were excluded. This ultimately led to the identification of a core group of five widely used species restricted to the Himalayan region (Cedrus deodara, Nardostachys jatamansi, Pinus wallichiana, Pinus roxburghii and Valeriana jatamansi). CONCLUSIONS: Here we apply a novel approach comprising an assessment of the published information on the use of medicinal plants (i.e. local and traditional knowledge) in the context of their potential to be used in a biomedical form of clinical treatment - aPDT. Then, once sustainable sourcing based on access and benefit-sharing arrangements is in place, these species are investigated for their potential in wound treatment. Ultimately, the goal is to develop a new baseline for primary health care in some of the regions of the world with poor or limited access to health care.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Plantas Medicinais , Infecção dos Ferimentos/terapia , Etnofarmacologia/métodos , Etnofarmacologia/tendências , Humanos , Medicina Tradicional do Leste Asiático/métodos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia
14.
Cancers (Basel) ; 13(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668625

RESUMO

BACKGROUND: Rodent cancer models have limitations in predicting efficacy, tolerability and accompanying biomarkers of ICIs in humans. Companion dogs suffering from neoplastic diseases have gained attention as a highly relevant translational disease model. Despite successful reports of PD-1/PD-L1 blockade in dogs, no compounds are available for veterinary medicine. METHODS: Here, we assessed suitability of seven FDA-approved human ICIs to target CTLA-4 or PD-1/PD-L1 in dogs. Cross-reactivity and blocking potential was assessed using ELISA and flow cytometry. Functional responses were assessed on peripheral blood mononuclear cells (PBMCs) derived from healthy donors (n = 12) and cancer patient dogs (n = 27) as cytokine production after stimulation. Immune composition and target expression of healthy donors and cancer patients was assessed via flow cytometry. RESULTS: Four candidates showed cross-reactivity and two blocked the interaction of canine PD-1 and PD-L1. Of those, only atezolizumab significantly increased cytokine production of healthy and patient derived PBMCs in vitro. Especially lymphoma patient PBMCs responded with increased cytokine production. In other types of cancer, response to atezolizumab appeared to correlate with a lower frequency of CD8 T cells. CONCLUSIONS: Cross-functionality of atezolizumab encourages reverse translational efforts using (combination) immunotherapies in companion dog tumor patients to benefit both veterinary and human medicine.

15.
Front Pharmacol ; 11: 594591, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117182

RESUMO

INTRODUCTION: Harmful usage of tobacco is a public health problem of global concern and, in many countries, the main risk factor for non-communicable diseases. Yet, in the Peruvian Amazon, the geographical region believed to be tobacco's historical birthplace, this plant is associated with a strikingly different usage and repute: Tobacco (especially Nicotiana rustica L.) in this area is described as a potent medicinal plant, used topically or via ingestion to treat a variety of health conditions. The goal of this transdisciplinary field study was to investigate clinical applications of the tobacco plant as per Amazonian medicine exemplified in the practice of a reputed Maestro Tabaquero, an Amazonian traditional healer whose medical specialization focuses on tobacco-based treatments. METHODS: Using a transdisciplinary clinical approach, we conducted in-depth interviews with the tabaquero applying the systematizing expert interview method, in order to map modes of preparation and administration, indications, contraindications, effects, risks, adverse effects, and systemic aspects of tobacco-based remedies. RESULTS: The informant's descriptions revealed refined knowledge on this plant's therapeutic properties and scope, safety profile, and application techniques. The main indications mentioned included "problems of the mind," of the respiratory system, parasitic illnesses (intestinal/skin), gout, and Amazonian epistemic conditions described as spiritual-energetic in nature. A liquid remedy taken orally was his most commonly used preparation, with acute/sub-acute effects involving a pronounced psychoactive component (altered state of consciousness) and physiological response (emesis, nausea). A skilled tabaquero that knows how to dose, administer, and intervene in case of adverse effects was considered imperative for safe treatment delivery. CONCLUSIONS: To our knowledge, this is the first study employing a transdisciplinary clinical approach to examine therapeutic applications of tobacco by an Amazonian tabaquero. Our findings significantly contribute to the growing research literature on Amazonian medicine and emergent psychedelic-assisted therapies and could, in the long-term, open new treatment avenues in several domains. Forthcoming studies should assess toxicity/safety and clinical outcomes of patients receiving Amazonian tobacco-based treatment.

16.
Chem Commun (Camb) ; 56(92): 14373-14376, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33140750

RESUMO

Novel tetraplatinated metalloporphyrin-based photosensitizers (PSs) are reported, which show excellent phototoxic indexes (PIs) up to 5800 against HeLa cells, which is, to the best of our knowledge, the highest value reported for any porphyrin so far. Furthermore, 67Zn isotope labelling allowed the determination of the ratio of zinc to platinum inside the cells using ICP-MS.


Assuntos
Metaloporfirinas/química , Fármacos Fotossensibilizantes/química , Platina/química , Isótopos de Zinco/química , Cobre/química , Células HeLa , Humanos , Marcação por Isótopo , Ligantes , Espectrometria de Massas , Metaloporfirinas/efeitos adversos , Imagem Óptica , Fotoquimioterapia , Fármacos Fotossensibilizantes/efeitos adversos , Platina/efeitos adversos , Relação Estrutura-Atividade , Distribuição Tecidual
17.
Front Pharmacol ; 11: 765, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581783

RESUMO

BACKGROUND: Global challenges related to access and benefit sharing (ABS) of biological resources have become a key concern in the area of research on herbal medicines, ethnopharmacology, drug discovery, and the development of other high value products for which Intellectual Property protection can be secured. While the Convention on Biological Diversity (CBD, Rio 1992) has been recognized as a huge step forward, the implementation of the Nagoya Protocol (NP) and of new forms of collaboration often remain unresolved, especially in the context of "the fair and equitable sharing of benefits arising from the utilization of genetic resources" (Convention on Biological Diversity, 2011). The vision and the specific implementation of this international treaty vary from country to country, which poses additional challenges. AIMS: Using a case study approach, in this analysis we aim at understanding the specific opportunities and challenges for implementing international collaborations regarding ABS in six Latin American countries-Chile, Colombia, Guatemala, México, Panama, and Peru. Based on that analysis, we provide recommendations for the path ahead regarding international collaborations under ABS agreements in ethnopharmacological research. RESULTS AND DISCUSSIONS: The implementation of the NP varies in the six countries; and while they are all rich in biodiversity, access and benefit sharing mechanisms differ considerably. There is a need to engage in a consultation process with stakeholders, but this has often come to a halt. Institutional infrastructures to implement national policies are weak, and the level of knowledge about the NP and the CBD within countries remains limited. CONCLUSIONS: Different policies in the six countries result in very diverse strategies and opportunities relating to the equitable use of biodiversity. A long-term strategy is required to facilitate a better understanding of the treaties and the resulting opportunities for a fairer development and implementation of transparent national polices, which currently differ in the six countries. So far, the benefits envisioned by the CBD and the NP remain unfulfilled for all stakeholders involved including local communities.

18.
World J Urol ; 27(3): 411-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19145437

RESUMO

PURPOSE: Patients with benign prostatic hyperplasia (BPH) and bladder outlet obstruction (BOO) frequently develop lower urinary tract symptoms (LUTS). To elucidate the underlying pathomechanisms we focused on altered cellular communication between detrusor cells. METHODS: Bladder biopsies were collected from eight BPH patients with compensated BOO and from eight non-obstructed patients. Detrusor areas were separated by laser capture microdissection microscopy, and extracted RNA was subjected to quantitative RT-PCR for connexin43 and connexin45. Furthermore, localization of connexin45 and lysosome membrane associated protein 1 was studied by immunohistochemistry. RESULTS: We found the human detrusor to express connexin45 rather than connexin43. Compared to controls, connexin45 expression was not significantly changed in detrusors of obstructed patients. However, connexin45 protein patterns were focally altered in obstruction. CONCLUSIONS: Our study is the first to provide evidence that connexin45-coupling of detrusor cells may be regionally impaired in patients with BOO due to BPH. The altered connexin45 coupling may contribute to LUTS.


Assuntos
Conexinas/biossíntese , Hiperplasia Prostática/complicações , Obstrução do Colo da Bexiga Urinária/etiologia , Obstrução do Colo da Bexiga Urinária/metabolismo , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
19.
ACS Appl Mater Interfaces ; 11(25): 22550-22560, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31203601

RESUMO

Photothermal therapy (PTT) using plasmonic nanoparticles for cancer treatment is on the verge of clinical application. Titanium nitride (TiN) nanoparticles offer a promising alternative to commonly used gold-based systems at a fraction of the costs. Little is known, however, about the relationship between TiN particle characteristics and their optical properties in colloidal systems. Here, TiN nanoparticles with closely controlled characteristics are prepared by nitridation of TiO2, and their use as PTT agents is explored. Emphasis is placed on the particle surface and core oxygen content, which dominate the TiN optical properties. Colloidal suspensions were studied under UV-vis and near-infrared (NIR) laser irradiation and correlated to particle characteristics. High nitridation temperatures and long residence times lead to increased NIR light absorption. Too high nitridation temperatures, however, lead to particle aggregation that deteriorated their optical properties. This was overcome with SiO2 coating of TiO2 nanoparticles prior to nitridation: the resulting SiO2-coated TiN particles exhibited increased plasmonic performance compared to bare TiN, which is attributed to reduced plasmonic coupling effects. The optimized SiO2-coated TiN had a photothermal efficiency of 58.5% and mass extinction coefficient of 31.6 L g-1 cm-1, outperforming commercial gold nanoshells that are used in clinical trials. The potential of SiO2-coated TiN for photothermal therapy was demonstrated by controllably killing HeLa cells in vitro.


Assuntos
Nanopartículas Metálicas/química , Dióxido de Silício/química , Titânio/química , Células HeLa , Humanos , Tamanho da Partícula
20.
Mol Cancer Res ; 5(12): 1263-75, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18171984

RESUMO

Colorectal cancers are believed to arise predominantly from adenomas. Although these precancerous lesions have been subjected to extensive clinical, pathologic, and molecular analyses, little is currently known about the global gene expression changes accompanying their formation. To characterize the molecular processes underlying the transformation of normal colonic epithelium, we compared the transcriptomes of 32 prospectively collected adenomas with those of normal mucosa from the same individuals. Important differences emerged not only between the expression profiles of normal and adenomatous tissues but also between those of small and large adenomas. A key feature of the transformation process was the remodeling of the Wnt pathway reflected in patent overexpression and underexpression of 78 known components of this signaling cascade. The expression of 19 Wnt targets was closely correlated with clear up-regulation of KIAA1199, whose function is currently unknown. In normal mucosa, KIAA1199 expression was confined to cells in the lower portion of intestinal crypts, where Wnt signaling is physiologically active, but it was markedly increased in all adenomas, where it was expressed in most of the epithelial cells, and in colon cancer cell lines, it was markedly reduced by inactivation of the beta-catenin/T-cell factor(s) transcription complex, the pivotal mediator of Wnt signaling. Our transcriptomic profiles of normal colonic mucosa and colorectal adenomas shed new light on the early stages of colorectal tumorigenesis and identified KIAA1199 as a novel target of the Wnt signaling pathway and a putative marker of colorectal adenomatous transformation.


Assuntos
Adenoma/genética , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Adenoma/patologia , Idoso , Biomarcadores Tumorais/metabolismo , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/patologia , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Filogenia , RNA Mensageiro/metabolismo , Transcrição Gênica
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