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1.
Cancer Control ; 29: 10732748221131000, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36355430

RESUMO

INTRODUCTION: The COVID-19 pandemic has disrupted many aspects of clinical practice in oncology, particularly regarding early cancer diagnosis, sparking public health concerns that possible delays could increase the proportion of patients diagnosed at advanced stages. In 2009, a cancer fast-track program (CFP) was implemented at the Clinico-Malvarrosa Health Department in Valencia, Spain with the aim of shortening waiting times between suspected cancer symptoms, diagnosis and therapy initiation. OBJECTIVES: The study aimed to explore the effects of the COVID-19 pandemic on our cancer diagnosis fast-track program. METHODS: The program workflow (patients included and time periods) was analysed from the beginning of the state of alarm on March 16th, 2020 until March 15th, 2021. Data was compared with data from the same period of time from the year before (2019). RESULTS: During the pandemic year, 975 suspected cancer cases were submitted to the CFP. The number of submissions only decreased during times of highest COVID-19 incidence and stricter lockdown, and overall, referrals were slightly higher than in the previous 2 years. Cancer diagnosis was confirmed in 197 (24.1%) cases, among which 33% were urological, 23% breast, 16% gastrointestinal and 9% lung cancer. The median time from referral to specialist appointment was 13 days and diagnosis was reached at a median of 18 days. In confirmed cancer cases, treatment was started at around 30 days from time of diagnosis. In total, 61% of cancer disease was detected at early stage, 20% at locally advanced stage, and 19% at advanced stage, displaying time frames and case proportions similar to pre-pandemic years. CONCLUSIONS: Our program has been able to maintain normal flow and efficacy despite the challenges of the current pandemic, and has proven a reliable tool to help primary care physicians referring suspected cancer patients.


Assuntos
COVID-19 , Neoplasias Pulmonares , Humanos , COVID-19/epidemiologia , Pandemias , Controle de Doenças Transmissíveis , Encaminhamento e Consulta , Neoplasias Pulmonares/diagnóstico
2.
J Oncol Pharm Pract ; 27(4): 1046-1051, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33040674

RESUMO

INTRODUCTION: Pembrolizumab is a monoclonal antibody approved for adult patients with advanced non-small-cell lung cancer (NSCLC). Although immune related adverse events are considered to be well tolerated, complications may occur and discontinuation of the treatment could be required. CASE REPORT: A 62-year old patient diagnosed with advanced non-small cell lung cancer experienced a decline in the renal function after seven cycles with pembrolizumab.Management & outcome: After ruling out other common causes of interstitial nephritis, pembrolizumab was attributed as a cause of interstitial nephritis. At first, toxicity was managed with corticosteroids and closely monitoring the patient, but finally pembrolizumab had to be discontinued due to the kidney function did not recover. DISCUSSION: Renal and urinary disorders were reported in <3% of patients treated with pembrolizumab, being interstitial nephritis the most reported toxicity. The kidney damage can be a complication to consider in patients receiving pembrolizumab. Early identification of an increase in serum creatinine levels may help with prevention by establishing an effective treatment, although it may not mean a total recovery of kidney function.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Nefrite Intersticial/induzido quimicamente , Nefrite Intersticial/diagnóstico por imagem , Anticorpos Monoclonais/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/sangue
3.
BMC Med Genet ; 20(1): 112, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234783

RESUMO

BACKGROUND: Septo-optic dysplasia (SOD), also known as de-Morsier syndrome, is a rare disorder characterized by any combination of optic nerve hypoplasia, pituitary gland hypoplasia, and midline abnormalities of the brain including absence of the septum pellucidum and corpus callosum dysgenesis. The variable presentation of SOD includes visual, neurologic, and/or hypothalamic-pituitary endocrine defects. The unclear aetiology of a large proportion of SOD cases underscores the importance of identifying novel SOD-associated genes. CASE PRESENTATION: To identify the disease-causing gene in a male infant with neonatal hypoglycaemia, dysmorphic features, and hypoplasia of the optic nerve and corpus callosum, we designed a targeted next-generation sequencing panel for brain morphogenesis defects. We identified a novel hemizygous deletion, c.6355 + 4_6355 + 5delAG, in intron 38 of the FLNA gene that the patient had inherited from his mother. cDNA studies showed that this variant results in the production of 3 aberrant FLNA transcripts, the most abundant of which results in retention of intron 38 of FLNA. CONCLUSIONS: We report for the first time a case of early-onset SOD associated with a mutation in the FLNA gene. This finding broadens the spectrum of genetic causes of this rare disorder and expands the phenotypic spectrum of the FLNA gene.


Assuntos
Filaminas/genética , Estudos de Associação Genética , Mutação , Displasia Septo-Óptica/genética , Sequência de Bases , Encéfalo , Corpo Caloso/diagnóstico por imagem , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Nervo Óptico , RNA Mensageiro/metabolismo , Displasia Septo-Óptica/diagnóstico por imagem , Displasia Septo-Óptica/fisiopatologia , Septo Pelúcido
4.
J Helminthol ; 88(1): 20-3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23046767

RESUMO

Predation by the mite Lasioseius penicilliger was studied on three nematode species, i.e. infective larval stages (L3) of Haemonchus contortus and adults of Panagrellus redivivus and Rhabditis sp. Experiments were carried out in 5.5-cm diameter Petri dishes containing 2% water-agar over a period of 5 days. Batches of up to 1500 third-stage larvae (L3) of H. contortus and 1000 adult nematodes of P. redivivus and Rhabditis sp. were exposed to five mites in separate Petri dishes. Upon contact, each mite used its pedipalp and legs to identify and hold its prey and then used its chelicerae to feed upon the prey. Predation by L. penicilliger was chance dependent but mites became aggregated around any injured/damaged prey, thereby suggesting some form of chemoperception. The rate of predation on the three species of nematodes was high but L3 of H. contortus and adult Rhabditis sp. were preferred.


Assuntos
Ácaros e Carrapatos/fisiologia , Rabditídios/parasitologia , Animais , Parasitologia/métodos , Comportamento Predatório
5.
Nanotechnology ; 23(1): 015707, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22155967

RESUMO

We report on the electrical transport properties of single multiwall carbon nanotubes with and without an iron filling as a function of temperature and magnetic field. For the iron filled nanotubes the magnetoresistance shows a magnetic behavior induced by iron, which can be explained by taking into account a contribution of s-d hybridization. In particular, ferromagnetic-like hysteresis loops were observed up to 50 K for the iron filled multiwall carbon nanotubes. The magnetoresistance shows quantum interference phenomena such as universal conductance fluctuations and weak localization effects.


Assuntos
Ferro/química , Nanotubos de Carbono/química , Condutividade Elétrica , Campos Magnéticos , Imãs/química , Nanotubos de Carbono/ultraestrutura , Temperatura
6.
Nanotechnology ; 23(28): 285701, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22717547

RESUMO

We have modified single walled carbon nanotubes (SWCNTs) with well defined matrix-based architectures to improve interface interaction in SWCNT/epoxy composites. The hardener and two pre-synthesized oligomers containing epoxy and hardener moieties were covalently attached to the SWCNT walls by in situ diazonium or carboxylic coupling reactions. In this way, SWCNTs bearing amine or epoxide-terminated fragments of different molecular weights, which resemble the chemical structure of the cured resin, were synthesized. A combination of characterization techniques such as Raman and infrared absorption (FTIR) spectroscopy, elemental analysis and coupled thermogravimetry-FTIR spectroscopy were used to identify both the functional groups and degree of functionalization of SWCNTs synthesized by the laser ablation and arc-discharge methods. Depending on the type of reaction employed for the chemical functionalization and the molecular weight of the attached fragment, it was possible to control the degree of functionalization and the electronic properties of the functionalized SWCNTs. Improved dispersion of SWCNTs in the epoxy matrix was achieved by direct integration without using solvents, as observed from optical microscopy and rheology measurements of the SWCNT/epoxy mixtures. Composite materials using these fillers are expected to exhibit improved properties while preserving the thermosetting architecture.

7.
Eur J Cancer ; 161: 26-37, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902765

RESUMO

BACKGROUND: The potential benefit of adding palbociclib to fulvestrant as first-line treatment in hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative endocrine-sensitive advanced breast cancer (ABC) patients remains uncharacterized. PATIENTS AND METHODS: In this randomized (1:1), double-blind, phase II study, postmenopausal women with HR-positive, HER2-negative ABC with de novo metastatic disease or those who relapsed after >12 months of adjuvant endocrine therapy received palbociclib/fulvestrant or placebo/fulvestrant. Stratification was based on recurrent versus de novo metastatic disease and visceral involvement. The primary objective was one-year progression-free survival (PFS-1y) rate. The sample size was 190 patients. The two-sided alpha of 0.2, 80% of power to detect a difference between the arms, assuming PFS rates of 0.695 and 0.545 for palbociclib/fulvestrant and placebo/fulvestrant, respectively. RESULTS: In total, 189 patients were randomized to palbociclib/fulvestrant ([n = 94] or placebo/fulvestrant [n = 95]). 45.5% and 60.3% of patients had de novo metastatic disease and visceral involvement, respectively. PFS-1y rates were 83.5% and 71.9% in the palbociclib/fulvestrant and placebo/fulvestrant arms, (HR 0.55, 80% CI 0.36-0.83, P = 0.064). The median PFS were 31.8 and 22.0 months for the palbociclib/fulvestrant and placebo/fulvestrant arms (aHR 0.48, 80% CI 0.37-0.64, P = 0.001). The most frequent grade 3-4 adverse events were neutropenia (68.1% vs. 0%), leucopenia (26.6% vs. 0%), anemia (3.2% vs. 0%), and lymphopenia (14.9% vs. 2.1%) for the palbociclib/fulvestrant and placebo/fulvestrant, respectively. The most frequent non-hematologic grade 3-4 adverse event was fatigue (4.3% vs. 0%). CONCLUSIONS: Palbociclib/fulvestrant demonstrated better PFS-1y rates and median PFS than placebo/fulvestrant in HR-positive/HER2-negative endocrine-sensitive ABC patients.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Fulvestranto/uso terapêutico , Piperazinas/uso terapêutico , Piridinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Fulvestranto/farmacologia , Humanos , Pessoa de Meia-Idade , Piperazinas/farmacologia , Piridinas/farmacologia
8.
Semergen ; 47(4): 240-247, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33865695

RESUMO

BACKGROUND: In the Community of Madrid since 2005 vaccination against pneumococcus in adults from 60 years of age has been carried out with pneumococcal polysaccharide vaccine (PPV23). In January 2018, the guideline changed in favor of pneumococcal conjugate vaccine (PCV13). The objective of this study was to analyze the data of pneumococcal vaccination and to evaluate the implementation of the new guideline of vaccination against pneumococcus in adults in the Community of Madrid. METHODS: Cross-sectional study to estimate vaccine coverage by a retrospective review of the record of vaccination history of people ≥60 years resident in the Community of Madrid. RESULTS: In the Community of Madrid until 2018, 83% of the population were vaccinated with PPV23, 6% with PCV13 and 11% with both vaccines. 96.5% came from Primary Care records. The doses administered of PCV13 surpassed those of PPV23 in ≥60 years in all age groups. 78,660 people ≥60 years were vaccinated with PCV13 (19.5% without risk factors, 67.3% with chronic diseases, 2.5% of the high-risk group and 10.7% belonging to both groups). CONCLUSIONS: In 2018, following Community of Madrid recommendations, 6,639 people were not properly vaccinated with PCV13 and 72,021 (91.6%) were properly vaccinated. The greatest confusion occurred in people ≥60 years without risk factors who had a previous PPV23 and did not require another vaccine but received a PCV13 without complying with the recommended schedule.


Assuntos
Infecções Pneumocócicas , Vacinas Pneumocócicas , Adulto , Idoso , Estudos Transversais , Humanos , Estudos Retrospectivos , Espanha , Vacinação
9.
ESMO Open ; 6(3): 100148, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33989988

RESUMO

BACKGROUND: Cancer is the second leading cause of mortality worldwide. Integrating different levels of care by implementing screening programmes, extending diagnostic tools and applying therapeutic advances may increase survival. We implemented a cancer fast-track programme (CFP) to shorten the time between suspected cancer symptoms, diagnosis and therapy initiation. PATIENTS AND METHODS: Descriptive data were collected from the 10 years since the CFP was implemented (2009-2019) at the Clinico-Malvarrosa Health Department in Valencia, Spain. General practitioners (GPs), an oncology coordinator and 11 specialists designed guidelines for GP patient referral to the CFP, including criteria for breast, digestive, gynaecological, lung, urological, dermatological, head and neck, and soft tissue cancers. Patients with enlarged lymph nodes and constitutional symptoms were also considered. On identifying patients with suspected cancer, GPs sent a case proposal to the oncology coordinator. If criteria were met, an appointment was quickly made with the patient. We analysed the timeline of each stage of the process. RESULTS: A total of 4493 suspected cancer cases were submitted to the CFP, of whom 4019 were seen by the corresponding specialist. Cancer was confirmed in 1098 (27.3%) patients: breast cancer in 33%, urological cancers in 22%, gastrointestinal cancer in 19% and lung cancer in 15%. The median time from submission to cancer testing was 11 days, and diagnosis was reached in a median of 19 days. Treatment was started at a median of 34 days from diagnosis. CONCLUSIONS: The findings of this study show that the interval from GP patient referral to specialist testing, cancer diagnosis and start of therapy can be reduced. Implementation of the CFP enabled most patients to begin curative intended treatment, and required only minimal resources in our setting.


Assuntos
Clínicos Gerais , Neoplasias Pulmonares , Humanos , Oncologia , Atenção Primária à Saúde , Encaminhamento e Consulta
10.
Plant Cell Rep ; 29(6): 661-71, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20376670

RESUMO

A procedure for inducing somatic embryos in shoot apex explants (2 mm) excised from shoot proliferation cultures established from adult oak trees (Quercus robur) was investigated. Embryogenesis was induced in shoot tip as well as leaf explants in three out of the five genotypes evaluated. Somatic embryos were formed by culture in induction medium supplemented with 21.48 muM naphthalene acetic acid and 2.22 muM benzyladenine for 8 weeks, and successive transfer of explants to expression media with a low concentration of growth regulators and without them. Both types of explants formed callus tissue from which somatic embryos developed, indicating indirect embryogenesis. Although the embryogenic frequencies were lower than 12%, it did not prevent the establishment of clonal embryogenic lines maintained by repetitive embryogenesis. Histological study confirmed an indirect somatic embryogenesis process from shoot tip explants, in which leaf primordia and the corresponding axial zones were involved in generating callus, whereas the apical meristem itself did not proliferate. The origin of embryogenic cells appeared to be associated with dedifferentiation of certain parenchymal cells in callus regions after transfer of explants to expression media without auxin. Division of embryogenic cells gave rise to proembryo aggregates of unicellular origin, although a multicellular origin from bulging embryogenic areas would also seem possible. Further development led to the formation of cotyledonary-stage somatic embryos and nodular embryogenic structures that may be considered as anomalous embryos with no clear bipolarity. Inducement of somatic embryos from explants isolated from shoot cultures ensures plant material all year round, thus providing a significant advantage over the use of leaf explants from field-grown trees.


Assuntos
Quercus/embriologia , Técnicas de Cultura de Tecidos/métodos , Divisão Celular , Meios de Cultura , Desenvolvimento Embrionário , Reguladores de Crescimento de Plantas/farmacologia , Brotos de Planta/embriologia , Brotos de Planta/crescimento & desenvolvimento , Quercus/crescimento & desenvolvimento
11.
Colloids Surf B Biointerfaces ; 185: 110612, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31740327

RESUMO

Given the potential applications of fluorescent carbon nanoparticles in biomedicine, the relationship between their chemical structure, optical properties and biocompatibility has to be investigated in detail. In this work, different types of fluorescent carbon nanoparticles are synthesized by acid treatment, sonochemical treatment, electrochemical cleavage and polycondensation. The particle size ranges from 1 to 6 nm, depending on the synthesis method. Nanoparticles that were prepared by acid or sonochemical treatments from graphite keep a crystalline core and can be classified as graphene quantum dots. The electrochemically produced nanoparticles do not clearly show the graphene core, but it is made of heterogeneous aromatic structures with limited size. The polycondensation nanoparticles do not have CC double bonds. The type of functional groups on the carbon backbone and the optical properties, both absorbance and photoluminescence, strongly depend on the nanoparticle origin. The selected types of nanoparticles are compatible with human intestinal cells, while three of them also show activity against colon cancer cells. The widely different properties of the nanoparticle types need to be considered for their use as diagnosis markers and therapeutic vehicles, specifically in the digestive system.


Assuntos
Carbono/química , Intestinos/patologia , Nanopartículas/química , Nanomedicina Teranóstica , Células CACO-2 , Fluorescência , Humanos , Nanopartículas/ultraestrutura , Fenômenos Ópticos , Espectroscopia Fotoeletrônica , Espectroscopia de Prótons por Ressonância Magnética , Pontos Quânticos/química , Espectrometria de Fluorescência , Espectrofotometria Infravermelho
12.
Nanotechnology ; 20(31): 315707, 2009 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-19597256

RESUMO

The effect of polyetherimide (PEI) as a compatibilizing agent on the morphology, thermal, electrical and dynamic mechanical properties of poly(ether ether ketone) (PEEK)/single-walled carbon nanotube (SWCNT) nanocomposites, has been investigated for different CNT loadings. After a pre-processing step based on ball milling and pre-mixing under mechanical treatment in ethanol, the samples were prepared by melt extrusion. A more homogeneous distribution of the CNTs throughout the matrix is found for composites containing PEI, as revealed by scanning electron microscopy. Thermogravimetric analysis demonstrates an increase in the matrix degradation temperatures under dry air and nitrogen atmospheres with the addition of SWCNTs; the level of thermal stability of these nanocomposites is maintained when PEI is incorporated. Both differential scanning calorimetry and synchrotron x-ray scattering studies indicate a slight decrease in the crystallization temperatures of the compatibilized samples, and suggest the existence of reorganization phenomena during the heating, which are favoured in the composites incorporating the compatibilizer, due to their smaller crystal size. Dynamic mechanical studies show an increase in the glass transition temperature of the nanocomposites upon the addition of PEI. Furthermore, the presence of PEI causes an enhancement in the storage modulus, and hence in the rigidity of these systems, attributed to an improved interfacial adhesion between the reinforcement and the matrix. The electrical and thermal conductivities of these composites decrease with the incorporation of PEI. Overall, the compatibilized samples exhibit improved properties and are promising for their use in industrial applications.

13.
J Nanosci Nanotechnol ; 9(10): 6055-63, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19908494

RESUMO

Single walled carbon nanotubes (SWNT) have been incorporated into a polypropylene (PP) matrix in different concentrations (range: 0.25-2.5 wt%). The nanotubes were blended with PP particles (approximately 500 microm in size) before mixing in an extruder. Finally, rectangular plates were obtained by compression moulding. PP-SWNT composites were gamma irradiated at different doses, 10 and 20 kGy, to promote crosslinking in the matrix and potentially enhance the interaction between nanotubes and PP. Extensive thermal, structural and mechanical characterization was conducted by means of DSC, X-ray diffraction, Raman spectroscopy, uniaxial tensile tests and dynamic mechanical thermal (DMTA) techniques. DSC thermograms reflected higher crystallinity with increasing nanotube concentration. XRD analysis confirmed the only presence of a monoclinic crystals and proved unambiguously that CNTs generated a preferred orientation. Raman spectroscopy confirmed that the intercalation of the polymer between bundles is favored at low CNTs contents. Elastic modulus results confirmed the reinforcement of the polypropylene matrix with increasing SWNT concentration, although stiffness saturation was observed at the highest concentration. Loss tangent DMTA curves showed three transitions for raw polypropylene. While gamma relaxation remained practically unchanged in all the samples, beta relaxation temperatures showed an increase with increasing CNT content due to the reduced mobility of the system. Gamma-irradiated PP exhibited an increase in the beta relaxation temperature, associated with changes in glass transition due to radiation-induced crosslinking. On the contrary, gamma-irradiated nanocomposites did not show this effect probably due to the reaction of radiative free radicals with CNTs.

14.
J Nanosci Nanotechnol ; 9(10): 6104-12, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19908501

RESUMO

Arc discharge single walled carbon nanotubes were processed by acid treatment, dispersion in a Pluronic F68 block copolymer aqueous solution and centrifugation. The as-prepared material was characterized by transmission electron microscopy, X-ray diffraction and Raman spectroscopy, showing an important degree of debundling as well as the removal of most of the graphitic and metallic impurities from pristine nanotubes. The nanotube-Pluronic material was integrated into an advanced trifunctional epoxy resin, triglycidyl p-aminophenol, using 4,4'-diaminodiphenylsulfone as the curing agent. The material was incorporated into the epoxy system (0.1, 0.25, 0.50, 1.0, 2.0 wt%) throughout hot magnetic stirring and ultrasonication. Curing kinetics was studied using differential scanning calorimetry, applying the Vyazovkin's isoconversional method. In the early stages of curing, the kinetic study revealed a decrease in the activation energy for samples containing Pluronic, suggesting that Pluronic induced an improvement in the mobility of reactants. The cured composites were characterized by Raman spectroscopy, thermogravimetric analysis and scanning electron microscopy. Micrographs revealed successful integration and homogeneous distribution of the nanotube-Pluronic material in the epoxy matrix, while direct integration of bare nanotubes originated aggregates and inhomogeneity.

15.
J Nanosci Nanotechnol ; 9(10): 6120-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19908503

RESUMO

Nylon-6/single-walled carbon nanotube (SWNT) nanocomposites with different SWNTs loadings were prepared by melt-blending. An efficient dispersion of SWNTs into the nylon-6 matrix was confirmed by scanning electron microscopy. DSC and time-resolved synchrotron X-ray diffraction were used to provide detailed information on the effect of SWNTs on the crystalline phase transition of nylon-6 in the nanocomposites. The incorporation of SWNTs accelerated the crystallization rate of nylon-6 due to a nucleating effect. The variable-temperature WAXS experiments, in both neat nylon-6 and nylon-6 nanocomposites, showed that the crystallization from the melt occured through the formation of the pseudo-hexagonal crystal form (gamma) and its transformation to the monoclinic form (alpha) on cooling. Additionally, this crystalline transition was reversible as observed upon heating. The alpha-gamma crystalline transformation temperature of nylon-6 was dependent on heating rate and, more importantly, on the SWNT content.

16.
J Nanosci Nanotechnol ; 9(10): 6164-70, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19908510

RESUMO

Multi-walled carbon nanotubes were highly aggregated into ropes after their synthesis by chemical vapour deposition and, therefore, two different methods for disentangling the bundles of nanotubes were studied. One method compared the use of mild and vigorous mechanical treatments in ethanol and the other one employed dispersants in aqueous media. For comparison purposes and according to their different exfoliating behaviour, sodium dodecyl sulphate and gum arabic were selected as dispersants. The results evidenced that mechanical sonication was insufficient for disentangling the ropes, whereas, the combined action of mild sonication in an ultrasonic bath with the addition of gum arabic to an aqueous suspension containing nanotubes improved the exfoliating performance. Stable suspensions of unbundled multi-walled carbon nanotubes were obtained adding only 0.05 wt% of gum arabic with a dispersant/MWNTs concentration ratio of 0.25. These values corresponded to a reduction in the dispersant concentration between 1 to 2 orders of magnitude compared to those commonly employed. In addition, a processing route for manufacturing dense and homogenous silicon nitride composites using spark plasma sintering with 1.8 vol% of multi-walled carbon nanotubes almost free of organics was developed without nanotubes degradation and aggregation.

17.
Cryo Letters ; 29(6): 493-504, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19280053

RESUMO

This study reports on the cryostorage of embryogenic lines derived from selected mature Quercus robur trees, following application of the PVS2-vitrification based procedure. In seven oak genotypes, embryo recovery levels ranging from 57-92% were obtained when 4-6 mg embryo clumps were precultured for 3 days on 0.3 M sucrose basal medium, treated with PVS2 solution for 60 min at 24 degrees C, and then immersed in liquid nitrogen (LN). Embryos of six out of seven lines were cryostored for one week and one year and used to evaluate cryopreservation tolerance, germination ability and to assess genetic fidelity by random amplified polymorphic DNA (RAPD) markers. There were no significant differences between the recovery frequencies of samples retrieved from LN after 1 week and 1 year of cryostorage. In five out of six lines, RAPD profiles of cryopreserved somatic embryos and regenerated plantlets were identical to those of the controls. Although polymorphisms were detected in only one cryostored embryo of one genotype, no genetic instability was found in the regenerated plantlets. This methodology appears to be suitable for long-term storage of this valuable germplasm, as the recovered plantlets were found to be genetically stable.


Assuntos
Criopreservação/métodos , Germinação/genética , Quercus/embriologia , Quercus/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , DNA de Plantas , Polimorfismo Genético , Sementes/genética
18.
An Pediatr (Barc) ; 69(6): 572-6, 2008 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-19128772

RESUMO

The objective of this study was to investigate the possible relationship between the presence of anogenital warts (AGW) in children and the sexual abuse as mode of transmission. Our series includes 8 patients with AGW who were treated in our hospital during the year 2007. A complete physical examination was carried out, including colposcopy or anoscopy, and samples were taken for histopathological examination and human papiloma virus (HPV) subtyping. We considered perinatal transmission as a possible route in two cases. Although sexual abuse was definitively confirmed in only one case, we observed some findings in four cases that led us to consider the possibility of sexual abuse. We did not consider the possibility of heteroinoculation or autoinoculation from common warts in any case. Our results have demonstrated the difficulty in assessing with certainty the source of HPV contamination in children with AGW.


Assuntos
Doenças do Ânus/patologia , Doenças do Ânus/virologia , Condiloma Acuminado/patologia , Condiloma Acuminado/virologia , Doenças dos Genitais Femininos/patologia , Doenças dos Genitais Femininos/virologia , Doenças dos Genitais Masculinos/patologia , Doenças dos Genitais Masculinos/virologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Prospectivos
19.
Farm Hosp ; 32(5): 261-73, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-19150041

RESUMO

OBJECTIVE: To investigate the prevalence of low-molecular-weight heparin (LMWH) prescription in venous thromboembolism prophylaxis in a general hospital and the suitability of the recommendations from the clinical practice guidelines. METHOD: A descriptive, observational and cross-sectional study of the indication-prescription type, carried out on patients admitted to medical departments and for surgery. RESULTS: 345 patients were included. The prevalence of HBPM use was 44.6% (95% CI, 39.3-50.1). Depending on the risk of thromboembolism, the decision to treat prophylactically (or not) was appropriate in 261 cases (75.7%; 95% CI, 70.7-80.1), and the action guidelines were not suitable for the remainder of patients. 55 patients (15.9%; 95% CI, 12.2-20.2) presented a high risk and were not prescribed prophylactically (underuse); and 29 patients (8.4%; 95% CI, 5.7-11.8) at low risk were treated prophylactically (overuse). There was a relationship between the appropriateness of the prescription and the type of patient (p<0.01). In the group of medical patients the prevalence of prescription was 22.6% (95% CI, 16.9-29.1) and only 33.3% of patients with a high to moderate risk of thromboembolism received prophylaxis. The prevalence of prescription in general surgery was 84.2% and 91.3% in traumatology. CONCLUSIONS: The degree of prophylaxis is adequate in surgical patients, but there was a significant percentage of medical patients with a high to moderate risk who did not receive suitable prophylaxis (underuse), despite recommendations with scientific and professional backing.


Assuntos
Anticoagulantes/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Tromboembolia Venosa/prevenção & controle , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Registros
20.
J Med Microbiol ; 67(7): 952-956, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29787364

RESUMO

PURPOSE: Cystic fibrosis (CF) patients are susceptible to infection with Achromobacter spp., although its clinical significance remains controversial. The aim of this study was to investigate the clinical impact of infection with Achromobacter spp. in CF patients. METHODS: CF outpatients with multiple sputum cultures and follow-up lung function tests were assigned to the case group (infected with Achromobacter spp.) or the control group (never infected with Achromobacter spp.) according to the isolation of Achromobacter spp. The Achromobacter spp. group included two subgroups, taking into consideration whether the isolation of Achromobacter spp. was intermittent or chronic. Baseline lung function tests and longitudinal behaviour were examined in relation to Achromobacter spp. status. RESULTS: A total of 190 CF patients were treated from January 2003 to December 2015 in the CF unit and 21 (11 %) had at least one positive culture for Achromobacter spp. Of these, 11/21 (52.4 %) patients were chronically infected with Achromobacter spp. An analysis of changes during follow-up showed the annual rate of FEV1 decline: -2.3±1.6 % in the Achromobacter spp. group compared to -1.1±0.9 % (P=0.02) in the control group. The chronically infected group also had a significantly greater decline in FEV1 compared to the control group (-2.9±1.9 vs -1.1±0.9; P=0.04). The mean number of annual pulmonary exacerbations during the study period was significantly higher in the case group (1.9±0.9 vs 1.1±0.8; P=0.03). CONCLUSIONS: The Achromobacter spp. status in CF shows a trend towards more severe airflow obstruction and an association with accelerated decline in lung function parameters.


Assuntos
Achromobacter/fisiologia , Fibrose Cística/fisiopatologia , Infecções por Bactérias Gram-Negativas/fisiopatologia , Pulmão/fisiopatologia , Infecções Respiratórias/fisiopatologia , Achromobacter/genética , Achromobacter/isolamento & purificação , Adolescente , Adulto , Fibrose Cística/microbiologia , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Pulmão/microbiologia , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/microbiologia , Adulto Jovem
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