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1.
Chem Soc Rev ; 47(14): 5187-5233, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-29901663

RESUMO

After about three decades of development, the polyol process is now widely recognized and practised as a unique soft chemical method for the preparation of a large variety of nanoparticles which can be used in important technological fields. It offers many advantages: low cost, ease of use and, very importantly, already proven scalability for industrial applications. Among the different classes of inorganic nanoparticles which can be prepared in liquid polyols, metals were the first reported. This review aims to give a comprehensive account of the strategies used to prepare monometallic nanoparticles and multimetallic materials with tailored size and shape. As regards monometallic materials, while the preparation of noble as well as ferromagnetic metals is now clearly established, the scope of the polyol process has been extended to the preparation of more electropositive metals, such as post-transition metals and semi-metals. The potential of this method is also clearly displayed for the preparation of alloys, intermetallics and core-shell nanostructures with a very large diversity of compositions and architectures.

2.
Hepatogastroenterology ; 55(88): 2125-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19260490

RESUMO

BACKGROUND/AIMS: Among spinal cord injury patients, digestive disorders are frequent, chronic, and progressive. Constipation and fecal incontinence, the most common disorders, can severely affect the quality of life of patients with spinal cord injury (SCI). METHODOLOGY: For this retrospective study, we reviewed the medical records of spinal cord injury patients with an intestinal stoma formation and developed a questionnaire to assess patient quality of life. Between January 1, 1996, and December 31, 2005, 10 SCI patients had a stoma formation for constipation, 10 for wound management, and 3 for other causes. Most of these stomas were performed by laparoscopy, with no postoperative mortality. RESULTS: Postoperative morbidity was 26% at the general level, with a rate of 4% at the local level; morbidity reached 56% at longer follow-up. The average period of bowel dysfunction was 7.2 years. The average time per week spent on bowel management (bowel care and defecation time) was 6 h prior to stoma formation, but decreased to 1.5 h afterwards. Half of the questionnaire respondents reported an improved quality of life. CONCLUSIONS: A left colostomy is an effective and safe alternative for anorectal disorders among SCI patients. For a large percentage of patients, it ensures an improved quality of life.


Assuntos
Colostomia , Constipação Intestinal/complicações , Constipação Intestinal/cirurgia , Traumatismos da Medula Espinal/complicações , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Úlcera por Pressão/complicações , Úlcera por Pressão/cirurgia , Qualidade de Vida , Fístula Retal/complicações , Fístula Retal/cirurgia , Estudos Retrospectivos , Inquéritos e Questionários , Adulto Jovem
3.
Clin Vaccine Immunol ; 18(10): 1728-36, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21852547

RESUMO

Lot 89SF has been the reference standard serum pool used in pneumococcal enzyme-linked immunosorbent assays (ELISAs) since 1990. In 2005, it was estimated that there remained between 2 and 5 years' supply of lot 89SF. Since lot 89SF was the reference standard used in the evaluation of the seven-valent pneumococcal conjugate vaccine Prevnar (PCV7), the link to clinical efficacy would be severed if stocks became completely depleted. Furthermore, demonstration of immune responses comparable to those elicited by PCV7 is a licensure approach used for new pneumococcal conjugate vaccines, so a replacement reference standard was required. A total of 278 volunteers were immunized with the 23-valent unconjugated polysaccharide vaccine Pneumovax II, and a unit of blood was obtained twice within 120 days following immunization. Plasma was prepared, pooled, and confirmed to be free from hepatitis B virus (HBV), hepatitis C virus (HCV), and HIV. The pooled serum was poured at 6 ml per vial into 15,333 vials and lyophilized. Immunological bridging of 007sp to 89SF was used to establish equivalent reference values for 13 pneumococcal capsular serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F) by five independent laboratories. Antibody concentrations in 007sp were established relative to the lot 89SF reference preparation using the WHO reference ELISA. Subsequently, 12 existing WHO calibration sera had concentrations reassigned for 13 pneumococcal serotypes using new serum 007sp as the reference, and these were compared to concentrations relative to the original reference serum. Agreement was excellent for the 12 WHO calibration sera. The 007sp preparation has replaced 89SF as the pneumococcal reference standard. Sufficient quantity of this new preparation is available such that, with judicious use, it should be available for at least 25 years.


Assuntos
Anticorpos Antibacterianos/sangue , Ensaio de Imunoadsorção Enzimática/normas , Streptococcus pneumoniae/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Experimentação Humana , Humanos , Vacinas Pneumocócicas/administração & dosagem , Padrões de Referência
4.
Eur Respir J ; 24(1): 24-9, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15293601

RESUMO

Lung cancer arises from multistep genetic damage of bronchial epithelium, driving multifocal progressive dysplastic lesions. However, the risk of progression of high-grade pre-invasive bronchial lesions to cancer is poorly assessed. The purpose of this study was to better define the parameters that predict the outcome of these lesions. The current authors prospectively studied 27 patients with 31 histologically proven severe dysplasia (SD) and carcinoma in situ (CIS), with repeated bronchoscopy and endobronchial treatment. The influence of respiratory-cancer history, histopathological classification, tobacco consumption, and number of biopsies on the progression rate into cancer was studied. The actuarial progression rate to cancer was 17% at 1 yr and 63% at 3 yrs. A total of 11 cases of CIS progressed to invasive cancer, 17 were stable or regressed during the study, two with SD regressed and one progressed to invasive cancer. Progression of CIS appeared more frequent in lesions diagnosed as "questionable CIS". Persistence of smoking did not influence high-grade lesion outcome. The existence of synchronous lung cancer did not seem to impact on progression. The number of biopsies did not influence the outcome. In conclusion, the current study suggests that the outcome of high-grade pre-invasive lesions is not modified by the number of biopsies performed on these lesions. Careful pathological examination of these lesions and pathological revision seem necessary, since questionable cases have the worse progression rate.


Assuntos
Carcinoma Broncogênico/patologia , Neoplasias Pulmonares/patologia , Invasividade Neoplásica/patologia , Lesões Pré-Cancerosas/patologia , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Broncoscopia/métodos , Carcinoma Broncogênico/mortalidade , Carcinoma Broncogênico/terapia , Distribuição de Qui-Quadrado , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Estadiamento de Neoplasias , Probabilidade , Prognóstico , Estudos Prospectivos , Estudos de Amostragem , Análise de Sobrevida , Fatores de Tempo
5.
Eur Respir J Suppl ; 39: 36s-44s, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12572700

RESUMO

Early detection of lung cancer requires none or few invasive techniques. Distal lung cancer (40% of the cases in most European countries) can be sensitively detected by spiral computed tomography. Theoretically, in 60% of cases, the proximal lesions (main to segmental bronchi, accessible by bronchoscopy) should be able to be detected by sputum cytology. Unfortunately, this very specific technique has a low sensitivity and is time consuming. Fluorescent bronchoscopy increases the detection rate of early or micro-invasive lesions and may be proposed in highly selected populations, but not as a screening test. Biomarkers in blood and sputum have not yet been clinically validated. However, the amount of data generated from studies first on resected tumours, then on early bronchial lesions and more recently on blood and sputum offer a wide field for investigation. Lung carcinogenesis is a multistep process characterised by the accumulation of successive molecular genetic and epigenetic abnormalities, resulting in selection of clonal cells with uncontrolled growth capacities throughout the whole respiratory tract (field cancerisation). Molecular lesions far precede morphological transformation of preneoplastic bronchial lesions (dysplasia) or alveolar lesions (atypical alveolar hyperplasia). Genetic and epigenetic abnormalities in the genes involved in cell cycle, senescence, apoptosis, repair, differentiation and cell migration control may be detected on bronchial biopsies, on respiratory cells from the sputum and even in the circulating deoxyribonucleic acid (DNA). The key genes involved include those in the P53-retinoblastoma (Rb) pathways. The balance between cyclin-dependent kinases and their inhibitors regulates the level of Rb phosphorylation and its function at G1-S transition; P53 plays at least two functions (cell cycle and apoptosis control). The balance of bax-bcl2 is important in the control of apoptosis as well as loss of fragile histidine triad expression. O(6)-methylguanine-DNA methyltransferase seems to be important in DNA repair control, the RARbeta receptor in differentiation, and cadherin H and E and different metalloproteases genes in cell migration. The demonstration of hyperexpression or silencing of these genes needs different validated techniques: immunohistochemistry on biopsies or cytological preparations, molecular biology techniques for mutations, loss of heterozygosity and aberrant methylation abnormalities. Automation and miniaturisation of these techniques will allow early detection and may be widely applied once clinically validated.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares/diagnóstico , Neoplasias Brônquicas/diagnóstico , Neoplasias Brônquicas/genética , Broncoscopia/métodos , DNA de Neoplasias/análise , Humanos , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/genética , Biologia Molecular , Mutação , Escarro/citologia , Tomografia Computadorizada Espiral/métodos
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