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1.
J Vet Cardiol ; 53: 60-71, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38705085

RESUMO

INTRODUCTION: To echocardiographically evaluate a large number of apparently healthy Czechoslovakian wolfdogs (CWDs) to identify possible subclinical cardiac abnormalities and to generate reference intervals. ANIMALS: One-hundred and seventeen apparently healthy client-owned CWDs. MATERIALS AND METHODS: Standard two-dimensional, M-mode, and Doppler echocardiographic measurements were obtained on non-sedated, manually restrained standing dogs. Animals with no relevant echocardiographic abnormalities were used to generate reference intervals. Echocardiographic variables were compared between males and females and between dogs with and without mitral regurgitation (MR). RESULTS AND DISCUSSION: Among the 117 CWDs, 103 dogs were used to generate reference intervals. The 14 dogs with abnormalities had more than trivial MR (12 dogs), subaortic stenosis (one dog), and equivocal subaortic stenosis (one dog). The 44 males were heavier than 59 females (P<0.001) and had a larger maximum left atrial dimension (P=0.015), left ventricular internal dimension at end-diastole (P<0.001) and systole (P<0.001), and thicker interventricular septum thickness at end-diastole (P=0.016). A positive linear correlation was identified between bodyweight and aortic root and left atrial diameters and left ventricular dimensions and between age and aortic root and left atrial diameter and peak late transmitral flow velocity. A negative linear correlation was identified between age and peak early transmitral flow velocity and the ratio between peak early and late transmitral flow velocities. No differences in echocardiographic-derived cardiac dimensions were detected between healthy dogs and dogs with more than trivial MR. CONCLUSIONS: In this population of CWDs, subclinical cardiac abnormalities were uncommon, and they were mainly classified as MR.

2.
Br J Dermatol ; 185(5): 988-998, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33959940

RESUMO

BACKGROUND: Genome-wide association studies (GWASs) have identified genes influencing skin ageing and mole count in Europeans, but little is known about the relevance of these (or other genes) in non-Europeans. OBJECTIVES: To conduct a GWAS for facial skin ageing and mole count in adults < 40 years old, of mixed European, Native American and African ancestry, recruited in Latin America. METHODS: Skin ageing and mole count scores were obtained from facial photographs of over 6000 individuals. After quality control checks, three wrinkling traits and mole count were retained for genetic analyses. DNA samples were genotyped with Illumina's HumanOmniExpress chip. Association testing was performed on around 8 703 729 single-nucleotide polymorphisms (SNPs) across the autosomal genome. RESULTS: Genome-wide significant association was observed at four genome regions: two were associated with wrinkling (in 1p13·3 and 21q21·2), one with mole count (in 1q32·3) and one with both wrinkling and mole count (in 5p13·2). Associated SNPs in 5p13·2 and in 1p13·3 are intronic within SLC45A2 and VAV3, respectively, while SNPs in 1q32·3 are near the SLC30A1 gene, and those in 21q21·2 occur in a gene desert. Analyses of SNPs in IRF4 and MC1R are consistent with a role of these genes in skin ageing. CONCLUSIONS: We replicate the association of wrinkling with variants in SLC45A2, IRF4 and MC1R reported in Europeans. We identify VAV3 and SLC30A1 as two novel candidate genes impacting on wrinkling and mole count, respectively. We provide the first evidence that SLC45A2 influences mole count, in addition to variants in this gene affecting melanoma risk in Europeans.


Assuntos
Melanoma , Envelhecimento da Pele , Adulto , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Envelhecimento da Pele/genética
3.
Leukemia ; 32(1): 139-148, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28663576

RESUMO

The molecular basis of advanced systemic mastocytosis (SM) is not fully understood and despite novel therapies the prognosis remains dismal. Exome sequencing of an index-patient with mast cell leukemia (MCL) uncovered biallelic loss-of-function mutations in the SETD2 histone methyltransferase gene. Copy-neutral loss-of-heterozygosity at 3p21.3 (where SETD2 maps) was subsequently found in SM patients and prompted us to undertake an in-depth analysis of SETD2 copy number, mutation status, transcript expression and methylation levels, as well as functional studies in the HMC-1 cell line and in a validation cohort of 57 additional cases with SM, including MCL, aggressive SM and indolent SM. Reduced or no SETD2 protein expression-and consequently, H3K36 trimethylation-was found in all cases and inversely correlated with disease aggressiveness. Proteasome inhibition rescued SETD2 expression and H3K36 trimethylation and resulted in marked accumulation of ubiquitinated SETD2 in SETD2-deficient patients but not in patients with near-normal SETD2 expression. Bortezomib and, to a lesser extent, AZD1775 alone or in combination with midostaurin induced apoptosis and reduced clonogenic growth of HMC-1 cells and of neoplastic mast cells from advanced SM patients. Our findings may have implications for prognostication of SM patients and for the development of improved treatment approaches in advanced SM.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Lisina/genética , Mastocitose Sistêmica/genética , Adulto , Idoso , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Feminino , Humanos , Células K562 , Masculino , Mastócitos/efeitos dos fármacos , Mastocitose/genética , Mastocitose Sistêmica/tratamento farmacológico , Metilação/efeitos dos fármacos , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Mutação/genética , Prognóstico , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/genética , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia
4.
Case Rep Hematol ; 2015: 737302, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25755899

RESUMO

Mast cell leukemia (MCL) is a very rare form of systemic mastocytosis (SM) with a short median survival of 6 months. We describe a case of a 65-year-old woman with aleukaemic variant of MCL with a very high serum total tryptase level of 2255 µg/L at diagnosis, which occurred following an episode of hypotensive shock. She fulfilled the diagnostic criteria of SM, with a bone marrow smear infiltration of 50-60% of atypical mast cells (MCs). She tested negative for the KIT D816V mutation, without any sign of organ damage (no B- or C-findings) and only few mediator-related symptoms. She was treated with antihistamine alone and then with imatinib for the appearance of anemia. She maintained stable tryptase level and a very indolent clinical course for twenty-two months; then, she suddenly progressed to acute MCL with a serum tryptase level up to 12960 µg/L. The patient died due to haemorrhagic diathesis twenty-four months after diagnosis. This clinical case maybe represents an example of the chronic form of mast cell leukemia, described as unpredictable disease, in which the serum total tryptase level has confirmed itself as a reliable marker of mast cells burden regardless of the presence of other signs or symptoms.

6.
Pathologica ; 104(2): 65-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22953502

RESUMO

BACKGROUND: While bronchoscopy should be considered in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) in which the cause cannot be determined from history or clinical and laboratory data, there are no studies about the utility of rapid on-site examination (ROSE) of broncho-alveolar lavage for identification, as early as possible, of the pathological condition underlying the onset of this condition. The aim of this prospective, observational study was to evaluate the diagnostic role of ROSE of BAL in ALI/ARDS. METHODS: 71 patients with ALI/ARDS underwent bronchoalveolar lavage, and one part of the sample was examined with ROSE. The on-site report was categorized as diagnostic (specific diagnosis), presence of atypical reactive type II pneumocytes with no further comments or not diagnostic. RESULTS: ROSE of bronco-alveolar lavage yielded 29 (41%) specific diagnoses, revealed typical features of diffuse alveolar damage without a specific diagnosis in 28 patients (39%) and did not reveal a specific diagnosis in the remaining 14 cases (20%). CONCLUSIONS: The results of this study show that, in patients with ALI/ARDS, bronchoalveolar lavage with ROSE is diagnostic in 40% of cases: ROSE may therefore spare lung biopsies and improve the prognosis of patients with ARDS (immunocompetent or not) as therapy could be started or modified at a very early phase.


Assuntos
Lesão Pulmonar Aguda/patologia , Líquido da Lavagem Broncoalveolar/citologia , Lavagem Broncoalveolar/métodos , Patologia Clínica/métodos , Síndrome do Desconforto Respiratório/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lavagem Broncoalveolar/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Patologia Clínica/instrumentação , Estudos Prospectivos , Adulto Jovem
7.
Eur Biophys J ; 38(7): 903-10, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19458948

RESUMO

Intermittent contact mode atomic force microscopy (AFM) was used to visualize the native plasma membrane of Xenopus laevis oocytes. Oocyte membranes were purified via ultracentrifugation on a sucrose gradient and adsorbed on mica leaves. AFM topographs and the corresponding phase images allowed for visualization and identification of both oocyte plasma membrane patches and pure lipid bilayer regions with a height of about 5 nm within membrane patches. The quantitative analysis showed a normal distribution for the lateral dimension and height of the protein complexes centered on 16.7 +/- 0.2 nm (mean +/- SE, n = 263) and 5.4 +/- 0.1 nm (n = 262), respectively. The phase signal, providing material-dependent information, allowed for the recognition of structural features observed in AFM topographs.


Assuntos
Membrana Celular/metabolismo , Oócitos/citologia , Xenopus laevis , Adsorção , Silicatos de Alumínio/química , Animais , Cristalografia por Raios X , Feminino , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Microscopia de Força Atômica , Sacarose/química , Fatores de Tempo , Ultracentrifugação
8.
MAGMA ; 22(2): 77-87, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18855033

RESUMO

OBJECT: Use of polyethylenimines (PEIs) of different molecular weight and selected carboxylated-PEI derivatives (PEI-COOH) in the synthesis and stabilization of iron oxide nanoparticles, to obtain possible multifunctional contrast agents. MATERIALS AND METHODS: Oxidation of Fe(II) at slightly elevated pH and temperature resulted in the formation of highly soluble and stable nanocomposites of iron oxides and polymer. Composites were characterized and studied by atomic force microscopy (AFM), transmission electron microscopy (TEM), X-ray diffractometry, AC and DC magnetometry, NMR relaxometry and magnetic resonance imaging (MRI). RESULTS: From AFM the dimensions of the aggregates were found to be in the ~150-250 nm size region; the mean diameter of the magnetic core of the compounds named PEI-25, PEI-500 and PEI-COOH60 resulted d approximately 20 +/- 5 nm for PEI-25, d approximately 9.5 +/- 1.0 nm for PEI-500 and d approximately 6.8 +/- 1.0 nm for PEI-COOH60. In PEI-COOH60 TEM and X-ray diffractometry revealed small assemblies of mineral magnetic cores with clear indications that the main constituents are maghemite and/or magnetite as confirmed by AC and DC SQUID magnetometry. For PEI-COOH60, the study of NMR-dispersion profiles revealed r (1) and r (2) relaxivities comparable to superparamagnetic iron-oxide commercial compounds in the whole investigated frequency range 7 < or = nu < or = 212 MHz. CONCLUSION: PEI-25 was studied as possible MRI contrast agent (CA) to map the cerebral blood volume (CBV) and cerebral blood flow (CBF) in an animal model obtaining promising results. The reported compounds may be further functionalized to afford novel multifunctional systems for biomedical applications.


Assuntos
Encéfalo/anatomia & histologia , Compostos Férricos/química , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Polietilenoimina/química , Animais , Meios de Contraste/química , Humanos , Ratos , Coloração e Rotulagem/métodos
9.
Ann Ig ; 20(5): 441-53, 2008.
Artigo em Italiano | MEDLINE | ID: mdl-19069250

RESUMO

A randomized stratified sample of 522 children attending the third class of primary schools within the area of Bologna Local Health Unit was analysed for physical activity and sports practice. Information about the children's habits and availability of facilities for physical and sports activities were collected by means of structured questionnaires completed by children (507 respondents), parents (491), reference teachers for physical education (26) and class teachers (46) during the school year 2006-07. At the same time, the children's heights and weights were measured in order to calculate BMI values. Regular sports activity is practised by 80.1% of children (males: 82.4%, females: 77.6%), with significant diferences between genders only in children with at least one non-Italian parent (M>F, p < 0.05); the practice of sports is influenced by the area of residence (metropolitan > plain and hills, p < 0.05) and nationality (Italians > non-Italians, p < 0.01). Children with at least one actively sports practising parent are involved more frequently in sports activities (p < 0.001). In free time, sedentary activities are prevalent for both sports-practising children and not. However children not involved in regular sports activities tend to practise outdoor physical activities with a frequency significantly higher than children involved in sports (17.3% vs 10.4% of respondents). The percentage of completely sedentary children, who stated that they practise neither sports nor physical activity in their free time, is 7.3% (metropolitan area: 4.5%, hills: 8.7%, plain: 10.6%). The prevalence of overweight is 24.4%, of obesity 9.7%, with a better distribution of BMI values in the metropolitan area where there is the highest occurrence of positive conditions and behaviours: availability of sports facilities, the highest prevalence of sports practice, and the lowest prevalence of completely sedentary children.


Assuntos
Exercício Físico/fisiologia , Esportes/estatística & dados numéricos , Fatores Etários , Índice de Massa Corporal , Criança , Interpretação Estatística de Dados , Feminino , Humanos , Itália , Estilo de Vida , Masculino , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Pais , Prevalência , Estudos de Amostragem , Fatores Sexuais , Inquéritos e Questionários
10.
Acta Psychiatr Scand ; 118(6): 490-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18759812

RESUMO

OBJECTIVE: To analyze the status of mental health research in 30 Latin American and Caribbean countries (LAC). METHOD: Medline and PsycInfo databases were searched to identify the LAC authors. Their publications were classified according to the topic, type of research and target population studied. Scientific indicators of these countries were assessed in other two different databases: Essential Scientific Information and Atlas of Science Project, both from Institute for Scientific Information. RESULTS: Indexed-publications were concentrated in six countries: Argentina, Brazil, Chile, Colombia, Mexico and Venezuela. Most studies dealt with the burdensome mental disorders but neglected important topics such as violence and other mental health priorities. CONCLUSION: Mental health research is mostly concentrated in a few LAC countries, but these countries would contribute to reduce the research gap, if they provide research training to their neighbors and engage in bi- or multi-lateral research collaboration on common region priorities.


Assuntos
Transtornos Mentais , Saúde Mental/estatística & dados numéricos , Editoração/estatística & dados numéricos , Pesquisa/estatística & dados numéricos , Comparação Transcultural , Bases de Dados Bibliográficas/estatística & dados numéricos , Educação/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Humanos , América Latina , Pesquisa/educação
11.
Microsc Res Tech ; 69(10): 826-34, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16886228

RESUMO

We used atomic force microscopy (AFM) to characterize the plasma membrane of Xenopus laevis oocytes. The samples were prepared according to novel protocols, which allowed the investigation of the extra- and intracellular sides of the membrane, both of which showed sparsely distributed spherical-like protrusions. Regions with comparably sized and densely packed structures arranged in an orderly manner were visualized and dimensionally characterized. In particular, two different arrangements, hexagonal and square packing, were recognizable in ordered regions. The lateral dimension of structures visualized on the external side had a normal distribution centered on 25.5 +/- 0.3 nm (mean value +/- SE), whereas that on the intracellular side showed a normal distribution centered on 30.2 +/- 0.8 nm. The height of the protrusions was 2-5 nm on the external side and 1-3 nm on the intracellular side. The mean number of structures on the external and intracellular sides of the plasma membrane was about 1000 microm(-2) and 850 microm(-2) respectively. Trypsin treatment greatly decreased the size of the membrane protrusions, thus confirming the proteic nature of the structures. These results show that AFM is a useful tool for structural characterization of proteins in a native eukaryotic membrane.


Assuntos
Membrana Celular/ultraestrutura , Microscopia de Força Atômica , Oócitos/ultraestrutura , Xenopus laevis/anatomia & histologia , Animais , Membrana Celular/efeitos dos fármacos , Técnicas de Preparação Histocitológica , Proteínas de Membrana/ultraestrutura , Oócitos/efeitos dos fármacos , Tripsina/farmacologia
12.
J Microsc ; 223(Pt 1): 57-65, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16872432

RESUMO

In this study we report an atomic force microscopy (AFM) investigation of the actin cortical cytoskeleton of Xenopus laevis oocytes. Samples consisted of inside-out orientated plasma membrane patches of X. laevis oocytes with overhanging cytoplasmic material. They were spread on a freshly cleaved mica surface, subsequently treated with Triton X-100 detergent and chemically fixed. The presence of actin fibres in oocyte patches was proved by fluorescence microscopy imaging. Contact mode AFM imaging was performed in air in constant force conditions. Reproducible high-resolution AFM images of a filamentous structure were obtained. The filamentous structure was identified as an actin cortical cytoskeleton, investigating its disaggregation induced by cytochalasin D treatment. The thinnest fibres showed a height of 7 nm in accordance with the diameter of a single actin microfilament. The results suggest that AFM imaging can be used for the high-resolution study of the actin cortical cytoskeleton of the X. laevis oocyte and its modifications mediated by the action of drugs and toxins.


Assuntos
Actinas/ultraestrutura , Citoesqueleto/ultraestrutura , Microscopia de Força Atômica , Oócitos/citologia , Oócitos/ultraestrutura , Xenopus laevis , Animais
14.
Thorax ; 61(5): 376-82, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16384881

RESUMO

BACKGROUND: Asthma exacerbation is the most common cause of hospital admission in children. A study was undertaken to investigate the importance of allergen exposure in sensitised individuals in combination with viral infections and other potentially modifiable risk factors precipitating asthma hospital admission in children. METHODS: Eighty four children aged 3-17 years admitted to hospital over a 1 year period with an acute asthma exacerbation (AA) were matched for age and sex with two control groups: stable asthmatics (SA) and children admitted to hospital with non-respiratory conditions (IC). Risk factors were assessed by questionnaires and determination of allergen sensitisation, home allergen exposure, pollen exposure, and respiratory virus infection. RESULTS: Several non-modifiable factors (atopy, duration of asthma) were associated with increased risk. Among the modifiable factors, pet ownership, housing characteristics, and parental smoking did not differ between the groups. Regular inhaled corticosteroid treatment was significantly less common in the AA group than in the SA group (OR 0.2, 95% CI 0.1 to 0.6; p = 0.002). A significantly higher proportion of the AA group were virus infected (44%) and sensitised and highly exposed to sensitising allergen (76%) compared with the SA (18% and 48%) and IC groups (17% and 28%; both p<0.001). In a multiple conditional logistic regression (AA v SA), allergen sensitisation and exposure or virus detection alone were no longer independently associated with hospital admission. However, the combination of virus detection and sensitisation with high allergen exposure substantially increased the risk of admission to hospital (OR 19.4, 95% CI 3.7 to 101.5, p<0.001). CONCLUSIONS: Natural virus infection and real life allergen exposure in allergic asthmatic children increase the risk of hospital admission. Strategies for preventing exacerbations will need to address these factors.


Assuntos
Alérgenos/efeitos adversos , Asma/etiologia , Hospitalização/estatística & dados numéricos , Viroses/complicações , Adolescente , Asma/terapia , Criança , Pré-Escolar , Poeira/análise , Feminino , Humanos , Exposição por Inalação/efeitos adversos , Masculino , Análise Multivariada , Fatores de Risco , Testes Cutâneos
15.
Monaldi Arch Chest Dis ; 61(1): 58-61, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15366338

RESUMO

The authors report a case of acute respiratory failure that fulfils the diagnostic criteria for acute eosinophilic pneumonia. Bronchoalveolar lavage eosinophilia and eosinophilic lung diseases are also discussed. The pathogenetic events, including the role of IL-5, eotaxin 1 and 2 and VEGF are emphasised.


Assuntos
Eosinofilia Pulmonar/etiologia , Insuficiência Respiratória/etiologia , Fumar/efeitos adversos , Doença Aguda , Anti-Inflamatórios/uso terapêutico , Broncoscópios , Feminino , Humanos , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Eosinofilia Pulmonar/diagnóstico por imagem , Eosinofilia Pulmonar/tratamento farmacológico , Insuficiência Respiratória/diagnóstico por imagem , Insuficiência Respiratória/tratamento farmacológico , Tomografia Computadorizada por Raios X , Resultado do Tratamento
16.
Arch Dis Child ; 89(6): 540-3, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15155399

RESUMO

AIMS: To investigate the relation between parentally reported wheeze (unconfirmed), physician confirmed wheeze, and subsequent lung function. METHODS: Children at risk of allergic disease (one parent atopic) were recruited antenatally and followed prospectively from birth. During the first three years of life parents were asked to contact the study team if their child was wheezy. The presence of wheeze was confirmed or not by the primary care or study physician. Respiratory questionnaire and specific airway resistance measurement (sR(aw), body plethysmograph) were completed at age 3 years. RESULTS: A total of 454 children were followed from birth to 3 years of age. One hundred and eighty six (40.9%) of the parents reported their child wheezing in the first three years of life, and in 130 (28.6%) the wheeze was confirmed. A total of 428 children attended the three year clinic review, of whom 274 (64%) successfully carried out lung function tests. There was no significant difference in sR(aw) (kPa.s; geometric mean, 95% CI) between children who had never wheezed (n = 152; 1.03, 1.00 to 1.06) and those with a parentally reported but unconfirmed wheeze (n = 36; 1.02, 0.96 to 1.07, p = 1.00). sR(aw) was significantly higher in children with a physician confirmed wheeze (n = 86; 1.17, 1.11 to 1.22, p < 0.001) compared to those with no history of wheeze or with unconfirmed wheeze. CONCLUSIONS: Children with physician confirmed wheeze have significantly poorer lung function compared to those with parentally reported but unconfirmed and those who have never wheezed. A proportion of parents may have little understanding of what medical professionals mean by the term "wheeze".


Assuntos
Pneumopatias/fisiopatologia , Sons Respiratórios/diagnóstico , Análise de Variância , Pré-Escolar , Medicina de Família e Comunidade , Seguimentos , Humanos , Lactente , Recém-Nascido , Pais , Estudos Prospectivos , Testes de Função Respiratória/métodos , Sons Respiratórios/fisiopatologia
17.
J Microsc ; 211(Pt 3): 249-55, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12950473

RESUMO

A comparative study of AFM and SEM imaging of the same area of a human scalp hair has been carried out to determine the similarity and the differences between the two techniques. Sample preparation for SEM analysis requires a metallization step and vacuum exposure, both of which could potentially induce modifications to the surface details. By contrast, AFM is a suitable technique to evaluate any effect resulting from sample manipulation because it can be applied without any specific treatment. AFM analysis demonstrates that sample metallization is responsible for modifications to the surface details of hair, mainly comprising an increase in height of scale steps and of root mean square roughness together with variation in scale profiles. Sample treatments for SEM imaging are in general potentially responsible for surface modifications to the samples involved.


Assuntos
Cabelo/ultraestrutura , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Varredura/métodos , Couro Cabeludo/ultraestrutura , Humanos
18.
J Control Release ; 90(3): 281-90, 2003 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-12880695

RESUMO

The beta- and gamma-irradiation effects on stability of microspheres made of poly(lactide-co-glycolide) 50:50 copolymer (PLGA) containing bupivacaine (BU) were studied. Microspheres containing 10, 25, and 40% w/w, respectively, of BU were prepared by spray drying and irradiated in air with beta- and gamma-irradiation at a dose of 25 kGy. Morphology (atomic force microscopy, particle-size analysis), physico-chemical characteristics (DSC and FT-IR spectroscopy), drug content and in vitro dissolution profile of microspheres were all determined; the stability of irradiated microspheres was evaluated over a 9-month period. The decrease of BU content in gamma-irradiated microspheres was almost always constant independent of the amount of BU per sample, therefore it was in inverse proportion to drug loading (range between 5 and 15%). BU release rate increased immediately after irradiation and increased slightly until 90 days of storage. As far as beta-irradiated microspheres are concerned, BU content decreased in a significant way (approximately 3%) only in microspheres containing 10% w/w of BU. Immediately after irradiation, drug release rate in beta-irradiated microspheres increased less than in the corresponding gamma-irradiated microspheres, and it did not change further over the following storage period. BU-loaded microspheres have been shown to be more stable against beta- than gamma-irradiation. AFM revealed that the surface roughness of the irradiated microspheres increases depending on irradiation. As such, if a parameter is quantifiable, it is proposed as a marker of degradation due to ionizing radiation.


Assuntos
Anestésicos Locais/química , Partículas beta , Bupivacaína/química , Raios gama , Glicolatos/efeitos da radiação , Varredura Diferencial de Calorimetria , Portadores de Fármacos , Estabilidade de Medicamentos , Glicolatos/química , Ácido Láctico , Microesferas , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Espectroscopia de Infravermelho com Transformada de Fourier , Esterilização/métodos , Temperatura , Fatores de Tempo
20.
Haematologica ; 85(8): 855-64, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10942933

RESUMO

The lung is one of the organs most severely affected by complications during the course of hematologic disorders. In the last years an impressive amount of progress has been made in clarifying the pathogenesis of lung diseases, particularly those occurring in conditions of severe immunosuppression such as bone marrow transplantion, acquired immunodeficiency syndrome or leukemia. Peculiar anatomical characteristics render the lung parenchyma highly susceptible to infections, but the clinical outcome is due not only to the injury induced by the pathogens but also to their interactions with inflammatory cells and particularly to the effects of a wide network of secreted cytokines. Polymorphonuclear cells, macrophages, lymphocytes and structural pulmonary cells (epithelial cells, interstitial cells) generate a variety of cytokines and growth factors which, in turn, may be responsible for the majority of the clinical effects in response to infections, such as those of Pneumocystis carinii and cytomegalovirus, but also to certain drugs or to radiation. The pathogenesis of graft-versus-host disease (GVHD) is still poorly understood, but animal models seem to demonstrate the involvement of a number of cytokines and growth factors, together with toxic effects induced by conditioning regimens.


Assuntos
Doenças Hematológicas/complicações , Pneumopatias/etiologia , Pulmão/patologia , Quimiotaxia de Leucócito , Citocinas/fisiologia , Suscetibilidade a Doenças , Doença Enxerto-Hospedeiro/complicações , Substâncias de Crescimento/fisiologia , Doenças Hematológicas/imunologia , Humanos , Pulmão/imunologia , Pneumopatias/induzido quimicamente , Pneumopatias/fisiopatologia , Linfócitos/fisiologia , Macrófagos Alveolares/fisiologia , Neutrófilos/fisiologia , Pneumonia/etiologia , Pneumonia/microbiologia , Pneumonia/virologia , Eosinofilia Pulmonar/etiologia , Pneumonite por Radiação/etiologia , Radioterapia/efeitos adversos , Condicionamento Pré-Transplante/efeitos adversos
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