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1.
Int J Mol Sci ; 23(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35408988

RESUMO

Pirfenidone, an antifibrotic drug, has antitumor potential against different types of cancers. Our work explored whether pirfenidone sensitizes non-small cell lung cancer (NSCLC) cell lines to chemotherapeutic treatments. The cytotoxic effect of paclitaxel in combination with pirfenidone against three NSCLC cell lines (A549, NCI-H322 and NCI-H460) was evaluated using the sulforhodamine B assay. The effects of this combination on cell viability (trypan blue exclusion assay), proliferation (BrdU incorporation assay), cell cycle (flow cytometry following PI staining) and cell death (Annexin V-FITC detection assay and Western blot) were analyzed on the most sensitive cell line (NCI-H460). The cytotoxic effect of this drug combination was also evaluated against two non-tumorigenic cell lines (MCF-10A and MCF-12A). Finally, the ability of pirfenidone to sensitize NCI-H460 cells to a combination of paclitaxel plus carboplatin was assessed. The results demonstrated that pirfenidone sensitized NCI-H460 cells to paclitaxel treatment, reducing cell growth, viability and proliferation, inducing alterations in the cell cycle profile and causing an increase in the % of cell death. Remarkably, this combination did not increase cytotoxicity in non-tumorigenic cells. Importantly, pirfenidone also sensitized NCI-H460 cells to paclitaxel plus carboplatin. This work highlights the possibility of repurposing pirfenidone in combination with chemotherapy for the treatment of NSCLC.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos/farmacologia , Apoptose , Carboplatina/farmacologia , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Pulmonares/metabolismo , Paclitaxel , Piridonas
2.
Arch Microbiol ; 203(7): 3751-3766, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34143270

RESUMO

The term extremophile was suggested more than 30 years ago and represents microorganisms that are capable of developing and living under extreme conditions, these conditions being particularly hostile to other types of microorganisms and to humankind. In terrestrial hydrothermal sites, like hot springs, "mud pools", solfataras, and geysers, the dominant extreme conditions are high temperature, low or high pH, and high levels of salinity. The diversity of microorganisms inhabiting these sites is determined by the conditions of the environment. Organisms belonging to the domains Archaea and Bacteria are more represented than the one belonging to Eukarya. Eukarya members tend to be less present because of their lower tolerance to higher temperatures, however, they perform important ecosystem processes when present. Both prokaryotes and eukaryotes have morphological and physical adaptations that allow them to colonize extreme environments. Microbial mats are complex associations of microorganisms that help the colonization of more extreme systems. In this review, a characterization of prokaryotic and eukaryotic organisms that populate terrestrial hydrothermal systems are made.


Assuntos
Archaea , Bactérias , Biodiversidade , Eucariotos , Fontes Termais , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Eucariotos/classificação , Eucariotos/genética
3.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1862(2): 156-166, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27815222

RESUMO

Neurospora crassa, a filamentous fungus, in the unicellular conidial stage has ideal features to study sphingolipid (SL)-enriched domains, which are implicated in fundamental cellular processes ranging from antifungal resistance to apoptosis. Several changes in lipid metabolism and in the membrane composition of N. crassa occur during spore germination. However, the biophysical impact of those changes is unknown. Thus, a biophysical study of N. crassa plasma membrane, particularly SL-enriched domains, and their dynamics along conidial germination is prompted. Two N. crassa strains, wild-type (WT) and slime, which is devoid of cell wall, were studied. Conidial growth of N. crassa WT from a dormancy state to an exponential phase was accompanied by membrane reorganization, namely an increase of membrane fluidity, occurring faster in a supplemented medium than in Vogel's minimal medium. Gel-like domains, likely enriched in SLs, were found in both N. crassa strains, but were particularly compact, rigid and abundant in the case of slime cells, even more than in budding yeast Saccharomyces cerevisiae. In N. crassa, our results suggest that the melting of SL-enriched domains occurs near growth temperature (30°C) for WT, but at higher temperatures for slime. Regarding biophysical properties strongly affected by ergosterol, the plasma membrane of slime conidia lays in between those of N. crassa WT and S. cerevisiae cells. The differences in biophysical properties found in this work, and the relationships established between membrane lipid composition and dynamics, give new insights about the plasma membrane organization and structure of N. crassa strains during conidial growth.


Assuntos
Membrana Celular/metabolismo , Membrana Celular/fisiologia , Lipídeos de Membrana/metabolismo , Neurospora crassa/crescimento & desenvolvimento , Neurospora crassa/metabolismo , Esfingolipídeos/metabolismo , Esporos/metabolismo , Parede Celular/metabolismo , Parede Celular/fisiologia , Proteínas Fúngicas/metabolismo , Fluidez de Membrana/fisiologia , Membranas/metabolismo , Membranas/fisiologia , Neurospora crassa/fisiologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Esporos/crescimento & desenvolvimento , Esporos/fisiologia , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Esporos Fúngicos/fisiologia
4.
J Econ Entomol ; 109(1): 445-53, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26357843

RESUMO

Four common Portuguese rice varieties--Thaibonnet, Gladio, Albatros, and Eurosis--were tested for their relative susceptibility to Sitophilus zeamais Motschulsky, a common pest of stored rice in Portugal and in tropical countries. Physical (moisture content, hardness, length, and width) and chemical (by attenuated total reflection-Fourier transform infrared spectroscopy) properties of rice kernels were measured. Insect bioassays measured median developmental time, Dobie's index of susceptibility, percentage of damaged grains and weight loss, and progeny developed. This was done for paddy, brown rice, and polished rice for each variety. There were small, but significant, differences in insect resistance among the varieties. However, it was different for paddy and polished rice. In paddy, these differences were correlated with hull damage, and Eurosis was the most susceptible variety. In polished rice, resistance was correlated with hardness, and Thaibonnet was the most susceptible variety. In general, paddy rice was more resistant to insect attack, followed by polished rice and then brown rice. Paddy kernels selected with undamaged hull were completely resistant to attack. Implications for IPM and breeding for resistant varieties are discussed.


Assuntos
Antibiose , Armazenamento de Alimentos , Oryza/genética , Gorgulhos/fisiologia , Animais , Grão Comestível/genética , Grão Comestível/fisiologia , Comportamento Alimentar , Feminino , Masculino , Oryza/fisiologia , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Support Care Cancer ; 21(7): 2033-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23435626

RESUMO

OBJECTIVE: The purpose of this work is to study the prevalence, intensity, and treatment of pain in Portuguese palliative care teams. METHODS: Twenty-one palliative care teams were invited to participate in a cross-sectional survey. Ten of these accepted and were included in the study. Data of all patients observed on the 18th week of 2011 were collected. The data collected concerning pain were: demographic data, pain intensity, drugs prescribed, and invasive techniques. The intensity of pain was rated using a five-point verbal rating scale from none to maximum. The Pain Management Index (PMI) was used to calculate the adequacy of the analgesia. RESULTS: A total of 164 patients were included in this study. One hundred fifty-one (92 %) had cancer. The median age was 71 years (16 to 95). Eighty-four (51 %) were females. Pain was directly assessed in 136 (83 %) of the patients, whereas 27 patients could not report pain because of cognitive failure. Of those directly assessed, 77 (57 %) had pain when they were assessed: 42 (55 %) mild, 25 (32 %) moderate, 9 (12 %) severe, and 1 (1 %) maximum. Non-opioid analgesics were used: paracetamol in 61 (37 %) and NSAID in 20 (12 %). Tramadol was the only opioid for mild to moderate pain used in 25 (15 %) patients. The opioids most used for moderate to intense pain were: morphine 74 (45 %), transdermal (TD) fentanyl 32 (20 %), and buprenorphine TD 28 (17 %). The adjuvants most used were: corticosteroids 38 (23 %), gabapentin 37 (23 %), and amitriptyline 15 (9 %). Only five (4 %) patients had a negative PMI, meaning an inadequate analgesia. CONCLUSION: The general prevalence of pain is similar to that reported by other. The prevalence of moderate to severe pain is also similar to that reported in other studies, although severe pain is somewhat lower than indicated in most reports. According to the PMI, pain control was acceptable to good.


Assuntos
Manejo da Dor/métodos , Dor/tratamento farmacológico , Dor/epidemiologia , Cuidados Paliativos/métodos , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Dor/etiologia , Manejo da Dor/estatística & dados numéricos , Medição da Dor/métodos , Portugal/epidemiologia , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-35010636

RESUMO

Acid Mine Drainage (AMD) results from sulfide oxidation, which incorporates hydrogen ions, sulfate, and metals/metalloids into the aquatic environment, allowing fixation, bioaccumulation and biomagnification of pollutants in the aquatic food chain. Acidic leachates from waste rock dams from pyritic and (to a lesser extent) coal mining are the main foci of Acid Mine Drainage (AMD) production. When AMD is incorporated into rivers, notable changes in water hydro-geochemistry and biota are observed. There is a high interest in the biodiversity of this type of extreme environments for several reasons. Studies indicate that extreme acid environments may reflect early Earth conditions, and are thus, suitable for astrobiological experiments as acidophilic microorganisms survive on the sulfates and iron oxides in AMD-contaminated waters/sediments, an analogous environment to Mars; other reasons are related to the biotechnological potential of extremophiles. In addition, AMD is responsible for decreasing the diversity and abundance of different taxa, as well as for selecting the most well-adapted species to these toxic conditions. Acidophilic and acidotolerant eukaryotic microorganisms are mostly composed by algae (diatoms and unicellular and filamentous algae), protozoa, fungi and fungi-like protists, and unsegmented pseudocoelomata animals such as Rotifera and micro-macroinvertebrates. In this work, a literature review summarizing the most recent studies on eukaryotic organisms and micro-organisms in Acid Mine Drainage-affected environments is elaborated.


Assuntos
Minas de Carvão , Poluentes Químicos da Água , Ácidos , Eucariotos , Rios , Sulfatos/análise , Poluentes Químicos da Água/análise
7.
J Telemed Telecare ; 27(6): 353-358, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31570034

RESUMO

INTRODUCTION: Continuous positive airway pressure is an effective treatment for obstructive sleep apnoea syndrome. However, positive airway pressure compliance rates are disappointingly low, so effective interventions are needed to improve compliance in sleep apnoea. Telemonitoring has been used to improve compliance, but results have been inconsistent. This study aimed to determine outcomes of telemonitoring positive airway pressure compliance and efficacy data compared to usual care and phone-call care. METHODS: Randomized controlled study in which 51 patients (82.4% male; between 25 and 78 years), diagnosed with moderate to severe obstructive sleep apnoea were consecutively randomized to usual care, weekly phone-call care or telemonitored care with the use of Restraxx™. All patients were submitted to a comprehensive educational programme during positive airway pressure adaptation. Patients were followed for the first four weeks of treatment with automatic positive airway pressure (AutoSet Spirit S8®; ResMed), and compliance and efficacy data were analyzed. RESULTS: Telemonitored care group used automatic positive airway pressure an average of 5.0 ± 1.8 hours/night, usual care patients 5.1 ± 2.5 hours and phone-call care patients 3.9 ± 2.6 hours. The residual Apnoea--Hypopnoea Index was 5.3 ± 3.0 in telemonitored care, 5.0 ± 2.5 in usual care and 5.6 ± 3.8 in phone-call care. No statistically significant differences were found between groups regarding positive airway pressure compliance or efficacy (p = 0.296 and p = 0.825, respectively). DISCUSSION: In the presence of a comprehensive educational programme during positive airway pressure adaptation, telemonitoring patients did not show benefits concerning compliance and efficacy. A larger follow-up period is needed to evaluate the long-term results of a telemonitoring programme.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Apneia Obstrutiva do Sono , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Projetos Piloto , Apneia Obstrutiva do Sono/terapia , Resultado do Tratamento
8.
Biomolecules ; 10(7)2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630112

RESUMO

The number of cases of failure in the treatment of infections associated with resistant bacteria is on the rise, due to the decreasing efficacy of current antibiotics. Notably, 7α-Acetoxy-6ß-hydroxyroyleanone (AHR), a diterpene isolated from different Plectranthus species, showed antibacterial activity, namely against Methicillin-resistant Staphylococcus aureus (MRSA) strains. The high antibacterial activity and low cytotoxicity render this natural compound an interesting alternative against resistant bacteria. The aim of this study is to understand the mechanism of action of AHR on MRSA, using the MRSA/Vancomycin-intermediate S. aureus (VISA) strain CIP 106760, and to study the AHR effect on lipid bilayers and on the cell wall. Although AHR interacted with lipid bilayers, it did not have a significant effect on membrane passive permeability. Alternatively, bacteria treated with this royleanone displayed cell wall disruption, without revealing cell lysis. In conclusion, the results gathered so far point to a yet undescribed mode of action that needs further investigation.


Assuntos
Diterpenos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Vancomicina/efeitos dos fármacos , Membrana Externa Bacteriana , Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos
9.
Front Cell Dev Biol ; 8: 337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32596234

RESUMO

Here, biophysical properties of membranes enriched in three metabolically related sterols are analyzed both in vitro and in vivo. Unlike cholesterol and ergosterol, the common metabolic precursor zymosterol is unable to induce the formation of a liquid ordered (l o) phase in model lipid membranes and can easily accommodate in a gel phase. As a result, Zym has a marginal ability to modulate the passive membrane permeability of lipid vesicles with different compositions, contrary to cholesterol and ergosterol. Using fluorescence-lifetime imaging microscopy of an aminostyryl dye in living mammalian and yeast cells we established a close parallel between sterol-dependent membrane biophysical properties in vivo and in vitro. This approach unraveled fundamental differences in yeast and mammalian plasma membrane organization. It is often suggested that, in eukaryotes, areas that are sterol-enriched are also rich in sphingolipids, constituting highly ordered membrane regions. Our results support that while cholesterol is able to interact with saturated lipids, ergosterol seems to interact preferentially with monounsaturated phosphatidylcholines. Taken together, we show that different eukaryotic kingdoms developed unique solutions for the formation of a sterol-rich plasma membrane, a common evolutionary trait that accounts for sterol structural diversity.

10.
Acta Med Port ; 31(12): 703-705, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30684366

RESUMO

Chronic obstructive pulmonary disease is a chronic condition that requires the engagement of our patients in lifestyle changes and pharmacological treatment. Although there are guidelines on many aspects of chronic obstructive pulmonary disease management, the challenge of engaging our patients persists. We propose a simple mnemonic that we hope will make it easier for patients and clinicians to achieve this goal together.


A doença pulmonar obstrutiva crónica é uma patologia crónica cujo tratamento depende do envolvimento dos doentes em mudanças de estilo de vida e tratamento farmacológico. Embora existam recomendações clínicas no tratamento da doença pulmonar obstrutiva crónica, o desafio em envolver os doentes persiste. Propomos uma mnemónica simples que esperamos contribuir para alcançar esse objetivo comum a médicos e doentes.


Assuntos
Abreviaturas como Assunto , Broncodilatadores/uso terapêutico , Estilo de Vida Saudável , Doença Pulmonar Obstrutiva Crônica/terapia , Ar , Broncodilatadores/classificação , Doença Crônica , Progressão da Doença , Dispneia/diagnóstico , Humanos , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/diagnóstico
11.
Am J Hosp Palliat Care ; 32(3): 335-40, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24463203

RESUMO

OBJECTIVE: To study the burden of patients' symptoms other than pain and their treatment by Portuguese palliative care teams. METHODS: Of the 21 Portuguese palliative care teams identified, 10 accepted to participate. Data from all patients observed on the 18th week of 2011 were collected. RESULTS: One hundred and sixty-four patients were included in this study. One hundred and fifty-one patients (92%) had cancer. The patients' median age was 71 years (16-95) and 84 (51%) were females. The main symptoms were fatigue (116 [85%]) and depression/sadness (107 [65%]). Many different drugs were used for symptom control and other aims. Symptoms and drugs used here are similar to those practiced in other countries. CONCLUSION: The practice of palliative care in Portugal seems to be similar to those in other countries.


Assuntos
Neoplasias/epidemiologia , Dor/epidemiologia , Cuidados Paliativos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Depressão/epidemiologia , Fadiga/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Conforto do Paciente , Portugal/epidemiologia , Adulto Jovem
12.
Am J Hosp Palliat Care ; 30(7): 648-51, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23264665

RESUMO

Of the 21 Portuguese teams identified, 10 accepted to participate in the study. A total of 164 patients were included with a median of 15.5 per team (4-32). Of all the patients included, 60 (37%) were identified as inpatients in palliative care units; 59 (36%) by an intrahospital support team; 26 (16%) as outpatients; and 19 (12%) at home. The median age was 71 years (16-95). Fifty-one percent were females. The diagnosis was cancer in 151 (92%) patients. The most common cancer was colorectal in 22 (15%) patients, followed by gastric 17 (11%), head and neck 17 (11%), breast 15 (10%), and lung cancers 14 (9%). All patients were treated by doctors and nurses experienced in palliative care.


Assuntos
Cuidados Paliativos , Inquéritos e Questionários , Estudos Transversais , Humanos , Neoplasias/terapia , Portugal
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