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1.
Cogn Res Princ Implic ; 9(1): 25, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652383

RESUMO

The use of face coverings can make communication more difficult by removing access to visual cues as well as affecting the physical transmission of speech sounds. This study aimed to assess the independent and combined contributions of visual and auditory cues to impaired communication when using face coverings. In an online task, 150 participants rated videos of natural conversation along three dimensions: (1) how much they could follow, (2) how much effort was required, and (3) the clarity of the speech. Visual and audio variables were independently manipulated in each video, so that the same video could be presented with or without a superimposed surgical-style mask, accompanied by one of four audio conditions (either unfiltered audio, or audio-filtered to simulate the attenuation associated with a surgical mask, an FFP3 mask, or a visor). Hypotheses and analyses were pre-registered. Both the audio and visual variables had a statistically significant negative impact across all three dimensions. Whether or not talkers' faces were visible made the largest contribution to participants' ratings. The study identifies a degree of attenuation whose negative effects can be overcome by the restoration of visual cues. The significant effects observed in this nominally low-demand task (speech in quiet) highlight the importance of the visual and audio cues in everyday life and that their consideration should be included in future face mask designs.


Assuntos
Sinais (Psicologia) , Percepção da Fala , Humanos , Adulto , Feminino , Masculino , Adulto Jovem , Percepção da Fala/fisiologia , Percepção Visual/fisiologia , Máscaras , Adolescente , Fala/fisiologia , Comunicação , Pessoa de Meia-Idade , Reconhecimento Facial/fisiologia
2.
BMC Oral Health ; 23(1): 657, 2023 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689626

RESUMO

BACKGROUND/INTRODUCTION: One of the key recommendations for the new WHO global strategy for oral health is inclusion of disadvantaged populations and their engagement in policy dialogues such that their needs and views are addressed in policy decisions. OBJECTIVES: This study explored oral health perceptions, practices and care-seeking experiences of slum residents in Ibadan, Nigeria. METHOD: Focus group discussions (FGD) were conducted with family health-decision makers in an urban slum site. Oral health perceptions, practices, and care-seeking experiences were discussed. FGDs were recorded, transcribed, and translated. ATLAS.ti qualitative research software was deployed for analysis using thematic analysis. RESULTS: Six FGD sessions, divided by gender and age, were conducted between September-October 2019, (N = total 58 participants, aged 25 to 59 years). Common dental ailments mentioned were dental pain, tooth sensitivity, bleeding gums, tooth decay, mouth odor, gum disease, and tooth fracture. Perceived causes of dental conditions included poor dental hygiene and habits, sugary diets, ignorance, and supernatural forces. Mouth cleaning was mostly done once daily using toothbrush and paste. Other cleaning tools were ground glass, wood ash, charcoal, "epa Ijebu" (a dentrifice), and "orin ata" (a type of chewing stick). Remedies for relieving dental pain included over-the-counter medicines, warm salted water, gin, tobacco (snuff/powdered), cow urine/dung, battery fluid, and various mixtures/ concoctions. Visits to the dentists were mentioned by a few but this was usually as last resort. Main barriers to accessing care from dental care facilities were unaffordability of service charges and fear of extreme treatment measures (extraction). Suggested measures to improve timely access to dental health care included reducing/subsidizing costs of treatments and medications, offering non-extraction treatment options, and oral health education programmes. CONCLUSION: The slum residents experience various forms of dental ailments mostly pain-related. The residents perceived formal dental clinics as unaffordable, thereby engaging in self-care remedies and harmful oral health practices before seeking professional help. Policymakers and decision-makers may leverage this empirical evidence for the people's education on early dental care and address challenges to affordable, available, and acceptable oral healthcare services among slum residents to improve access to care facilities.


Assuntos
Saúde Bucal , Áreas de Pobreza , Animais , Bovinos , Feminino , Nigéria , Escolaridade , Dor
3.
Int J Audiol ; : 1-13, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37363933

RESUMO

OBJECTIVE: Several viruses are known to have a negative impact on hearing health. The global prevalence of COVID-19 means that it is crucial to understand whether and how SARS-CoV2 affects hearing. Evidence to date is mixed, with studies frequently exhibiting limitations in the methodological approaches used or the populations sampled, leading to a substantial risk of bias. This study addressed many of these limitations. DESIGN: A comprehensive battery of measures was administered, including lab-based behavioural and physiological measures, as well as self-report instruments. Performance was thoroughly assessed across the auditory system, including measures of cochlear function, neural function and auditory perception. Hypotheses and analyses were pre-registered. STUDY SAMPLES: Participants who were hospitalised as a result of COVID-19 (n = 57) were compared with a well-matched control group (n = 40) who had also been hospitalised but had never had COVID-19. RESULTS: We find no evidence to support the hypothesis that COVID-19 is associated with deficits in auditory function on any auditory test measure. Of all the confirmatory analyses, only the self-report measure of hearing decline indicated any difference between groups. CONCLUSION: Results do not support the hypothesis that COVID-19 infection has a significant long-term impact on the auditory system.

4.
Clin Case Rep ; 11(1): e6563, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36619480

RESUMO

Tooth jewelry boosts the appearance and confidence of wearers. However, its use may carry adverse health consequences. This paper creates awareness about a practice not previously reported in Nigeria, to prevent negative health consequences while appropriate measures are taken to quantify and describe the determinants and plan appropriate interventions.

5.
J Public Health (Oxf) ; 44(1): e79-e87, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33348362

RESUMO

BACKGROUND: There is increasing prevalence of diseases associated with ageing such as hypertension, among people living with HIV (PLWHV). This study sought to assess: (1) knowledge related to HIV infection and hypertension, (2) adherence to prescribed medications and (3) clinical outcomes among HIV-positive persons with hypertension at a Nigerian hospital. METHODS: The Patient's HIV Knowledge Questionnaire (PHKQ), Hypertension Knowledge-Level Scale (HK-LS) and Adherence to Refills and Medication Scale (ARMS) were administered to 220 eligible patients through the HIV clinic. Demographic and clinical data were also obtained. RESULTS: Participants were predominantly females (57.3%), with a median (IQR) age of 46 (38-58) years; majority were married (67.8%) and employed (60.8%). Participants reported a higher hypertension-related knowledge compared with HIV-related knowledge (63.6% versus 33.3%, Z = -10.263, P < 0.001), but better adherence to antiretroviral medications compared to antihypertensives (100.0% versus 89.3%, Z = -9.118, P < 0.001). Of the 98 participants with documented viral load, 55 (56.1%) had undetectable (<40 copies/ml) values; however, only four (2.0%) of the entire sample had controlled (<140/90 mmHg) blood pressure. CONCLUSIONS: Despite having a higher hypertension-related knowledge, adherence to antihypertensive medications and blood pressure control were poor. There is a need for increased attention to HIV education and comorbidities in PLWHV.


Assuntos
Infecções por HIV , Hipertensão , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Masculino , Adesão à Medicação , Pessoa de Meia-Idade
6.
Public Health ; 196: 74-81, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34161858

RESUMO

OBJECTIVES: Breast cancer survivors have reported worse health-related quality of life (HRQoL) outcomes on some subscales when compared with members of the general population. However, the increased attention to breast cancer survivorship should have improved the HRQoL of these survivors. Our aim was to examine whether physical and mental component scores (PCS-12 and MCS-12) using the Short Form (SF-12) questionnaire were different for racial/ethnic minorities, specifically for Black and Hispanic women relative to White women. Furthermore, we stratified the data by age group to evaluate these racial/ethnic differences in HRQoL of breast cancer survivors. STUDY DESIGN: Cross-sectional study. METHODS: Pooled cross-sectional analyses using data from the Medical Expenditure Panel Survey between 2008 and 2016 were conducted. Pooled ordinary least squares (OLS) regression was used to examine the racial/ethnic differences in PCS-12 and MCS-12 scores of breast cancer survivors. Furthermore, stratified analyses by age group were conducted to evaluate racial/ethnic differences in HRQoL by the age of breast cancer survivors. RESULTS: After adjusting for confounders, there was no association between race/ethnicity and PCS-12 scores. However, Hispanic breast cancer survivors had statistically significantly lower MCS-12 scores (by 1.9 points [95% confidence interval {CI}: -3.53 to -0.37]) when compared with White breast cancer survivors. For PCS-12, after stratifying by age, the adjusted analyses showed no significant differences in PCS-12 scores when White female breast cancer survivors were compared with the other racial/ethnic categories. On the other hand, Black female survivors aged <50 years had 4.3 points (95% CI: 0.46-8.13) higher MCS-12 scores when compared with their White counterparts, while Hispanic breast cancer survivors aged <50 years had 3.1 points (95% CI: -0.40-6.69) higher MCS-12 scores relative to White women. Furthermore, among female breast cancer survivors aged ≥50 years, Hispanic women had 3.2 points (95% CI: -4.98 to -1.40) lower MCS-12 scores than White women. CONCLUSION: Our study generated findings showing the racial/ethnic differences in HRQoL of breast cancer survivors and presented results stratified by age group. These findings provide the much-needed rationale for targeted and racial/ethnic-specific HRQoL improvement strategies among breast cancer survivors.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Estudos Transversais , Feminino , Gastos em Saúde , Humanos , Qualidade de Vida , Inquéritos e Questionários
8.
J Phys Condens Matter ; 33(19)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33556928

RESUMO

The dispersion of inorganic particles within polymeric materials is an extensively used method to enhance their mechanical properties. One of the major challenges in the simulation of polymer composites is to model the uneven surface of the fillers which strongly affects the dynamics of the adsorbed polymers and consequently the macroscopic mechanical properties of the final composite. Here we propose a new multiscale approach that, using experimental adsorption data, constructs the filler surface to statistically reproduce the surface defects. We use this approach to analyse the structure and dynamics of highly entangled polyisoprene melt in contact with different realistic carbon black samples. We show that the presence of the heterogeneous surface has a negligible influence on the structure of the polymer chains but a major effect on their dynamics and the surface wettability.

9.
Sci Rep ; 10(1): 19390, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173219

RESUMO

AML is a genetically heterogeneous disease and understanding how different co-occurring mutations cooperate to drive leukemogenesis will be crucial for improving diagnostic and therapeutic options for patients. MIR142 mutations have been recurrently detected in IDH-mutated AML samples. Here, we have used a mouse model to investigate the interaction between these two mutations and demonstrate a striking synergy between Mir142 loss-of-function and IDH2R140Q, with only recipients of double mutant cells succumbing to leukemia. Transcriptomic analysis of the non-leukemic single and leukemic double mutant progenitors, isolated from these mice, suggested a novel mechanism of cooperation whereby Mir142 loss-of-function counteracts aberrant silencing of Hoxa cluster genes by IDH2R140Q. Our analysis suggests that IDH2R140Q is an incoherent oncogene, with both positive and negative impacts on leukemogenesis, which requires the action of cooperating mutations to alleviate repression of Hoxa genes in order to advance to leukemia. This model, therefore, provides a compelling rationale for understanding how different mutations cooperate to drive leukemogenesis and the context-dependent effects of oncogenic mutations.


Assuntos
Regulação Leucêmica da Expressão Gênica/fisiologia , Proteínas de Homeodomínio/metabolismo , Isocitrato Desidrogenase/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , MicroRNAs/metabolismo , Animais , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Feminino , Regulação Leucêmica da Expressão Gênica/genética , Genótipo , Proteínas de Homeodomínio/genética , Humanos , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/genética , Masculino , Camundongos , MicroRNAs/genética , Mutação/genética
10.
Health Phys ; 116(4): 503-515, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30652977

RESUMO

Radiation-induced lung injury is a delayed effect of acute radiation exposure resulting in pulmonary pneumonitis and fibrosis. Molecular mechanisms that lead to radiation-induced lung injury remain incompletely understood. Using a murine model of whole-thorax lung irradiation, C57BL/6J mice were irradiated at 8, 10, 12, and 14 Gy and assayed at day 1, 3, and 6 postexposure and compared to nonirradiated (sham) controls. Tryptic digests of lung tissues were analyzed by liquid chromatography-tandem mass spectrometry on a Waters nanoLC instrument coupled to a Thermo Scientific Q Exactive hybrid quadrupole-orbitrap mass spectrometer. Pathway and gene ontology analysis were performed with Qiagen Ingenuity, Panther GO, and DAVID databases. A number of trends were identified in the proteomic data, including protein changes greater than 10 fold, protein changes that were consistently up regulated or down regulated at all time points and dose levels interrogated, time and dose dependency of protein changes, canonical pathways affected by irradiation, changes in proteins that serve as upstream regulators, and proteins involved in key processes including inflammation, radiation, and retinoic acid signaling. The proteomic profiling conducted here represents an untargeted systems biology approach to identify acute molecular events that could potentially be initiating events for radiation-induced lung injury.


Assuntos
Lesão Pulmonar/metabolismo , Pulmão/efeitos da radiação , Proteômica , Lesões Experimentais por Radiação/metabolismo , Animais , Cromatografia Líquida , Relação Dose-Resposta à Radiação , Pulmão/metabolismo , Lesão Pulmonar/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espectrometria de Massas em Tandem
11.
J Intellect Disabil Res ; 62(11): 974-991, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30225989

RESUMO

BACKGROUND: Anxiety disorders have high prevalence in people with intellectual disabilities. In populations without intellectual disabilities, cognitive behavioural therapy is a first line psychological therapy for these presentations. There is no existing review of the range of methods and outcomes from intervention studies in this area. METHOD: A systematic review was carried out following guidance in the Cochrane handbook for systematic reviews of interventions. RESULTS: Nineteen studies were identified. The majority of reports were descriptive case studies; the most frequently described presentations were non-specific anxiety disorders and post-traumatic stress disorder; the most frequently described cognitive techniques were psycho-education and interventions directly aimed at thoughts and beliefs and most studies reported positive outcomes, although the better controlled studies tended to report less comprehensive impacts. CONCLUSIONS: A range of presentations have been described although the area is still at a primarily descriptive stage. We discuss intervention structures and approaches that require further research.


Assuntos
Transtornos de Ansiedade/terapia , Terapia Cognitivo-Comportamental/métodos , Comorbidade , Deficiência Intelectual/terapia , Adulto , Transtornos de Ansiedade/epidemiologia , Humanos , Deficiência Intelectual/epidemiologia
12.
Nature ; 555(7696): 355-358, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29542688

RESUMO

Lateral variations of seismic wave speeds and attenuation (dissipation of strain energy) in the Earth's upper mantle have the potential to map key characteristics such as temperature, major-element composition, melt fraction and water content. The inversion of these data into meaningful representations of physical properties requires a robust understanding of the micromechanical processes that affect the propagation of seismic waves. Structurally bound water (hydroxyl) is believed to affect seismic properties but this has yet to be experimentally quantified. Here we present a comprehensive low-frequency forced-oscillation assessment of the seismic properties of olivine as a function of water content within the under-saturated regime that is relevant to the Earth's interior. Our results demonstrate that wave speeds and attenuation are in fact strikingly insensitive to water content. Rather, the redox conditions imposed by the choice of metal sleeving, and the associated defect chemistry, appear to have a substantial influence on the seismic properties. These findings suggest that elevated water contents are not responsible for low-velocity or high-attenuation structures in the upper mantle. Instead, the high attenuation observed in hydrous and oxidized regions of the upper mantle (such as above subduction zones) may reflect the prevailing oxygen fugacity. In addition, these data provide no support for the hypothesis whereby a sharp lithosphere-asthenosphere boundary is explained by enhanced grain boundary sliding in the presence of water.

13.
Cir. mayor ambul ; 23(1): 23-27, ene.-mar. 2018. tab
Artigo em Inglês | IBECS | ID: ibc-173484

RESUMO

Introduction: The development of a new cohort of procedures suitable for Ambulatory Surgery has been recently mooted by the International Association of Ambulatory Surgery.This paper describes a ten year audit of performance of such operations in England, calculating rates for admission, treatment and discharge over the same calendar day. Methods: Data were extrapolated from NHS Digital information for the years 2006-7 to 2016-17, by subtracting emergency operations from the total number of finished consultant episodes, and then calculating the ambulatory surgery rate. Results: There has been a consistent increase in the rates of ambulatory surgery for the periods evaluated. Procedures can be divided into "mature", "rapidly rising" and "low threshold" categories, dependent upon their relative rates. Conclusion: Retrospective audit of ambulatory surgery performance allows assessment of national status to facilitate further development of the speciality


No disponible


Assuntos
Humanos , Procedimentos Cirúrgicos Ambulatórios/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Inglaterra , Auditoria Clínica/estatística & dados numéricos , Estudos Retrospectivos , Hospitalização/estatística & dados numéricos
14.
Radiat Res ; 185(5): 516-26, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27135969

RESUMO

Cerium oxide nanoparticles (CNPs) have a unique surface regenerative property and can efficiently control reactive oxygen/nitrogen species. To determine whether treatment with CNPs can mitigate the delayed effects of lung injury after acute radiation exposure, CBA/J mice were exposed to 15 Gy whole-thorax radiation. The animals were either treated with nanoparticles, CNP-18 and CNP-ME, delivered by intraperitoneal injection twice weekly for 4 weeks starting 2 h postirradiation or received radiation treatment alone. At the study's end point of 160 days, 90% of the irradiated mice treated with high-dose (10 µM) CNP-18 survived, compared to 10% of mice in the radiation-alone (P < 0.0001) and 30% in the low-dose (100 nM) CNP-18. Both low- and high-dose CNP-ME-treated irradiated mice showed increased survival rates of 40% compared to 10% in the radiation-alone group. Multiple lung functional parameters recorded by flow-ventilated whole-body plethysmography demonstrated that high-dose CNP-18 treatment had a significant radioprotective effect on lethal dose radiation-induced lung injury. Lung histology revealed a significant decrease (P < 0.0001) in structural damage and collagen deposition in mice treated with high-dose CNP-18 compared to the irradiated-alone mice. In addition, significant reductions in inflammatory response (P < 0.01) and vascular damage (P < 0.01) were observed in the high-dose CNP-18-treated group compared to irradiated-alone mice. Together, the findings from this preclinical efficacy study clearly demonstrate that CNPs have both clinically and histologically significant mitigating and protective effects on lethal dose radiation-induced lung injury.


Assuntos
Cério/química , Cério/farmacologia , Lesão Pulmonar/prevenção & controle , Nanopartículas/química , Lesões Experimentais por Radiação/prevenção & controle , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/efeitos da radiação , Feminino , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/efeitos da radiação , Lesão Pulmonar/patologia , Lesão Pulmonar/fisiopatologia , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Tamanho do Órgão/efeitos da radiação , Lesões Experimentais por Radiação/patologia , Lesões Experimentais por Radiação/fisiopatologia , Respiração/efeitos dos fármacos , Respiração/efeitos da radiação , Análise de Sobrevida
17.
Br Dent J ; 210(5): 207-11, 2011 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-21394145

RESUMO

The inferior alveolar nerve block or inferior dental block (IDB) is one of the most common techniques of delivering dental anaesthesia, with several million being administered each year. When conventional techniques fail the dentist should have the skills and confidence to use alternative techniques to achieve anaesthesia. The aim of this paper is to discuss the possible reasons for failure, with particular reference to local anatomy. The benefit of alternative techniques is highlighted by the use of an interesting case study, involving a superior position of the mandibular foramen.


Assuntos
Anestesia Dentária/métodos , Mandíbula/inervação , Nervo Mandibular , Bloqueio Nervoso/métodos , Adulto , Anestesiologia/educação , Educação em Odontologia , Feminino , Humanos , Mandíbula/anatomia & histologia , Mandíbula/cirurgia , Dente Serotino/cirurgia , Pericoronite/cirurgia , Dente Impactado/cirurgia
18.
Radiat Res ; 173(2): 165-74, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20095848

RESUMO

To investigate the relationship of HIF1alpha signaling to oxidative stress, tissue hypoxia, angiogenesis and inflammation, female Fischer 344 rats were irradiated to the right hemithorax with a fractionated dose of 40 Gy (8 Gy x 5 days). The lung tissues were harvested before and at 4, 6, 10, 14, 18, 22 and 26 weeks after irradiation for serial studies of biological markers, including markers for hypoxia (HIF1alpha, pimonidazole and CA IX), oxidative stress (8-OHdG), and angiogenesis/capillary proliferation (VEGF/CD 105), as well as macrophage activation (ED-1) and cell signaling/fibrosis (NFkappaB, TGFbeta1), using immunohistochemistry and Western blot analysis. HIF1alpha staining could be observed as early as 4 weeks postirradiation and was significantly increased with time after irradiation. Importantly, HIF1alpha levels paralleled oxidative stress (8-OHdG), tissue hypoxia (pimonidazole and CA IX), and macrophage accumulation consistent with inflammatory response. Moreover, changes in HIF1alpha expression identified by immunohistochemistry assay parallel the changes in TGFbeta1, VEGF, NFkappaB and CD 105 levels in irradiated lungs. These results support the notion that oxidative stress and tissue hypoxia might serve as triggering signals for HIF1alpha activity in irradiated lungs, relating to radiation-induced inflammation, angiogenesis and fibrosis.


Assuntos
Fracionamento da Dose de Radiação , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Pulmão/efeitos da radiação , Estresse Oxidativo , Transdução de Sinais , 8-Hidroxi-2'-Desoxiguanosina , Animais , Western Blotting , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Feminino , Imuno-Histoquímica , NF-kappa B/metabolismo , Neovascularização Patológica , Ratos , Ratos Endogâmicos F344 , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Aesthetic Plast Surg ; 33(3): 346-52, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19198927

RESUMO

BACKGROUND: Phosphatidylcholine formulation has been used to dissolve local fat deposits. This study aimed to evaluate and compare the effects of phosphatidylcholine formulation and its vehicle sodium deoxycholate alone on different cell lines to understand better its mechanism of action. METHODS: Cells and media including 3T3-L1 preadipocytes, normal foreskin fibroblasts, neonatal human dermal microvascular endothelial cells (CADMEC), and fetal human skeletal muscle cells (HSkMC) were used. After 24 h, cells were exposed in 3-4, 5-dimethylthiazol-2-yl-2, 3-diphenyl tetrazolium bromide reagent (MTT assays) to increasing dosages of phosphatidylcholine formulation (0.0156-0.5 mg/ml) or an equivalent vehicle, sodium deoxycholate solution, pH 9.0 (0.0066-0.210 mg/ml). Viability was assessed after 1, 2, and 3 days of treatment. Fat tissue (4 x 4 cm) obtained ex vivo from the dorsal fat pads of five rabbits was injected with 2 ml of phosphatidylcholine formulation (50 mg/ml), sodium deoxycholate (21 mg/ml), or normal saline and incubated for 24 h. These were examined histologically to identify cell lysis and morphologic changes. RESULTS: At 0.125- and 0.25-mg/ml doses of phosphatidylcholine solution, CADMEC and HSkMC were more sensitive (P < 0.001, one-way ANOVA) than adipocytes at all time points examined. Phosphatidylcholine formulation at a dose of 0.5 mg/ml and the equivalent vehicle, sodium deoxycholate, at a dose of 0.21-mg/ml both induced nearly 100% fat cell lysis after 24 h, and evidence of cell lysis as early as 6 h after exposure. After incubation of fat tissue for 24 h with phosphatidylcholine formulation, loss of intracellular lipid staining with an increase in extracellular lipids was seen. CONCLUSIONS: Isolated sodium deoxycholate was almost as effective as the phosphatidylcholine formulation, at clinical concentrations, in reducing the viability of mature adipocytes over time. Similar cytotoxic effects of phosphatidylcholine formulation on normal foreskin fibroblasts, endothelial cells, and human skeletal muscle cells also were observed. The data prove that the formulation acts in a nonspecific manner and that its unintentional administration to other tissues causes cell death.


Assuntos
Adipócitos/efeitos dos fármacos , Fosfatidilcolinas/farmacologia , Adipócitos/citologia , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colagogos e Coleréticos/administração & dosagem , Colagogos e Coleréticos/farmacologia , Colorimetria , Meios de Cultura , Ácido Desoxicólico/administração & dosagem , Ácido Desoxicólico/farmacologia , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Fibroblastos , Humanos , Técnicas In Vitro , Fosfatidilcolinas/administração & dosagem , Fosfatidilcolinas/química
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