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1.
Childs Nerv Syst ; 40(2): 603-605, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37874377

RESUMO

PURPOSE: Cerebral sinovenous thrombosis is an increasingly recognized cause of stroke in children and neonates. Its true incidence appears to be underestimated. Despite being a rare event, certain studies have found a correlation between subdural hemorrhage and cerebral sinus thrombosis. The literature suggests that spontaneous cerebral sinovenous thrombosis in the pediatric population may lead to the occurrence of a subdural hemorrhage. In this report, we present a case of cerebral venous thrombosis associated with chronic subdural hematoma and review the literature to highlight the importance of these conditions. CASE REPORT: An 11-year-old boy was admitted in the neurosurgery department with headache and a neurological examination without changes. The imaging studies identified a heterogeneous subdural collection in the fronto-temporo-parietal region. The patient underwent surgical drainage of the subdural hematoma, and the procedure was performed without complications. The magnetic resonance and angiography showed an extensive thrombosis of the superior sagittal sinus, extending downward to the occipital sinus and partially to the right transverse sinus. CONCLUSIONS: Appropriate management in the diagnosis and an early treatment of dural sinus thrombosis associated with subdural hemorrhage can reduce the risk of recurrence and improve the clinical outcome.


Assuntos
Cavidades Cranianas , Trombose dos Seios Intracranianos , Criança , Masculino , Recém-Nascido , Humanos , Hematoma Subdural/complicações , Hematoma Subdural/diagnóstico por imagem , Hematoma Subdural/cirurgia , Trombose dos Seios Intracranianos/complicações , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/cirurgia , Imageamento por Ressonância Magnética/efeitos adversos , Seio Sagital Superior/patologia
2.
J Appl Microbiol ; 124(3): 719-729, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29280549

RESUMO

AIMS: The preparation of the high-value flavour γ-dodecalactone is based on the biotransformation of natural 10-HSA, which is in turn obtained by microbial hydration of oleic acid. We want to establish a reliable baker's yeast-mediated procedure for 10-HSA preparation. METHODS AND RESULTS: The previously reported yeast-mediated hydration procedures are unreliable because bacteria-free baker's yeast is not able to hydrate oleic acid. The actual responsible for performing this reaction are the bacterial contaminants present in baker's yeast. Moreover, we demonstrated that the enantioselectivity in the production of (R)-10-HSA is affected mainly by the temperature used in the biotransformation. CONCLUSIONS: We demonstrated that Saccharomyces cerevisiae is not able to hydrate oleic acid, whereas different bacterial strains present in baker's yeast transform oleic acid into (R)-10-HSA. We reported a general procedure for the preparation of (R)-10-HSA starting from oleic acid and using commercially available baker's yeast. SIGNIFICANCE AND IMPACT OF THE STUDY: This study holds both scientific and industrial interest. It unambiguously establishes that the eukaryote micro-organisms present in baker's yeast are not able to hydrate oleic acid. The isolation of oleic acid hydrating bacterial strains from commercial baker's yeast points to their prospective use for the industrial synthesis of 10-HSA.


Assuntos
Ácido Oleico/metabolismo , Saccharomyces cerevisiae/metabolismo , Ácidos Esteáricos/metabolismo , Biotransformação , Fermentação
3.
Phys Chem Chem Phys ; 18(25): 16912-20, 2016 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-27282123

RESUMO

(1)H nuclear spin-lattice relaxation and Dynamic Nuclear Polarization (DNP) have been studied in amorphous samples of trehalose sugar doped with TEMPO radicals by means of mechanical milling, in the 1.6-4.2 K temperature range. The radical concentration was varied between 0.34 and 0.81%. The highest polarization of 15% at 1.6 K, observed in the sample with concentration 0.50%, is of the same order of magnitude of that reported in standard frozen solutions with TEMPO. The temperature and concentration dependence of the spin-lattice relaxation rate 1/T1, dominated by the coupling with the electron spins, were found to follow power laws with an exponent close to 3 in all samples. The observed proportionality between 1/T1 and the polarization rate 1/Tpol, with a coefficient related to the electron polarization, is consistent with the presence of Thermal Mixing (TM) and a good contact between the nuclear and the electron spins. At high electron concentration additional relaxation channels causing a decrease in the nuclear polarization must be considered. These results provide further support for a more extensive use of amorphous DNP-ready samples, obtained by means of comilling, in dissolution DNP experiments and possibly for in vivo metabolic imaging.

4.
Br J Cancer ; 113(6): 864-71, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26325106

RESUMO

BACKGROUND: Hypoxia is thought to be an adverse feature of pancreatic cancer, but direct measurement in patients is technically challenging. To address this, we characterised the intra/interpatient heterogeneity of hypoxia in surgical specimens from patients who received the 2-nitroimidazole tracer pimonidazole pre-operatively. METHODS: Pimondazole was given intravenously 16-20 h before pancreatectomy, and the extent and intratumoral heterogeneity of hypoxia determined by image analysis applied to multiple tissue blocks stained by immunohistochemistry. Intra/interpatient heterogeneity was estimated by variance component analysis. RESULTS: Pimonidazole staining was analysed in 10 tumours. The extent of labelling varied amongst patients (0-26%), with a broader range of hypoxia in the epithelial (1-39%) compared with the stromal (1-13%) compartments. Variance component analysis demonstrated greater inter- than intrapatient variability of hypoxia, and that multiple (4-5) tumour sections are required to provide a consistent evaluation of its extent in individual tumours. CONCLUSIONS: There is significant intra- and intertumoral heterogeneity of hypoxia in pancreatic cancers, and these do not appear to be generally more hypoxic than other cancer types. This study establishes the feasibility to assess hypoxia in pancreatic cancer patients using pimonidazole, but questions the reliability of measurements made using a single tissue section.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Hipóxia Celular , Indicadores e Reagentes/metabolismo , Nitroimidazóis/metabolismo , Neoplasias Pancreáticas/metabolismo , Adulto , Análise de Variância , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Imuno-Histoquímica , Indicadores e Reagentes/administração & dosagem , Injeções Intravenosas , Masculino , Nitroimidazóis/administração & dosagem , Pâncreas/metabolismo , Pancreatectomia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Pré-Medicação , Viés de Seleção
5.
Thorax ; 70(4): 346-52, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25766689

RESUMO

OBJECTIVE: To evaluate whether follow-up of patients with obstructive sleep apnoea (OSA) undergoing CPAP treatment could be performed in primary care (PC) settings. DESIGN: Non-inferiority, randomised, prospective controlled study. SETTINGS: Sleep unit (SU) at the University Hospital and in 8 PC units in Lleida, Spain. PARTICIPANTS: Patients with OSA were randomised to be followed up at the SU or PC units over a 6-month period. MAIN OUTCOMES MEASURED: The primary outcome was CPAP compliance at 6 months. The secondary outcomes were Epworth Sleep Scale (ESS) score, EuroQoL, patient satisfaction, body mass index (BMI), blood pressure and cost-effectiveness. RESULTS: We included 101 patients in PC ((mean±SD) apnoea-hypopnoea index (AHI) 50.8±22.9/h, age 56.2±11 years, 74% male) and 109 in the SU (AHI 51.4±24.4/h, age 55.8±11 years, 77% male)). The CPAP compliance was (mean (95% CI) 4.94 (4.47 to 5.5) vs 5.23 (4.79 to 5.66) h, p=0.18) in PC and SU groups, respectively. In the SU group, there were greater improvements in ESS scores (mean change 1.79, 95% CI +0.05 to +3.53, p=0.04) and patient satisfaction (-1.49, 95% CI -2.22 to -0.76); there was a significant mean difference in BMI between the groups (0.57, 95% CI +0.01 to +1.13, p=0.04). In the PC setting, there was a cost saving of 60%, with similar effectiveness, as well as a decrease in systolic blood pressure (-5.32; 95% CI -10.91 to +0.28, p=0.06). CONCLUSIONS: For patients with OSA, treatment provided in a PC setting did not result in worse CPAP compliance compared with a specialist model and was shown to be a cost-effective alternative. TRIAL REGISTRATION NUMBER: Clinical Trials NCT01918449.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Atenção Primária à Saúde/organização & administração , Apneia Obstrutiva do Sono/terapia , Adulto , Idoso , Pressão Positiva Contínua nas Vias Aéreas/economia , Análise Custo-Benefício , Atenção à Saúde/economia , Atenção à Saúde/organização & administração , Feminino , Seguimentos , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Assistência de Longa Duração/economia , Assistência de Longa Duração/organização & administração , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente/estatística & dados numéricos , Atenção Primária à Saúde/economia , Apneia Obstrutiva do Sono/economia , Espanha
6.
Knee Surg Sports Traumatol Arthrosc ; 23(2): 608-18, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25416674

RESUMO

PURPOSE: Massive rotator cuff tears (MRCT) are usually chronic lesions that present associated degenerative changes of the myotendinous unit that have been implicated in limitations for surgical repair. In order to develop effective therapies, it is important to establish animal models that mimic the hallmarks of the injury itself. Therefore, in the present work, we aimed to (1) optimize a rodent animal model of MRCT that closely reproduces the fatty infiltration of the cuff muscles seen in humans and (2) describe the effects of unilateral or bilateral lesion in terms of histology and behaviour. METHODS: Massive tear was defined as two rotator cuff tendons-supraspinatus and infraspinatus-section. Twenty-one Wistar rats were randomly assigned to four groups: bilateral lesion (five animals), right-sided unilateral lesion (five animals), left-sided unilateral lesion (five animals) and control (six animals). Behaviour was analyzed with open field and staircase test, 16 weeks after lesion. After that, animals were killed, and the supraspinatus and infraspinatus muscles were processed. RESULTS: Histologic analysis revealed adipocytes, fatty infiltration and atrophy in the injured side with a greater consistency of these degenerative changes in the bilateral lesion group. Behaviour analysis revealed a significant functional impairment of the fine motor control of the forepaw analyzed in staircase test where the number of eaten pellets was significantly higher in sham animals (sham = 7 ± 5.0; left unilateral = 2.6 ± 3.0; right unilateral = 0 ± 0; and bilateral = 0 ± 0, p < 0.05). A trend to reach a lower level of steps, in more injured animals, was also observed (sham animals = 3 ± 1.6 > left unilateral = 2 ± 2.1 > right unilateral = 0.8 ± 1.3 > bilateral = 0.8 ± 1.1). CONCLUSIONS: The present study has been able to establish an animal model that disclosed the hallmarks of MRCT. This can now be used as a valuable, cost-effective, pre-clinical instrument to assist in the development of advanced tissue engineered strategies. Moreover, this animal model overcomes some of the limitations of those that have been reported so far and thus represents a more reliable source for the assessment of future therapeutic strategies with potential clinical relevance.


Assuntos
Modelos Animais de Doenças , Lesões do Manguito Rotador , Manguito Rotador/patologia , Traumatismos dos Tendões/patologia , Animais , Doença Crônica , Masculino , Ratos , Ratos Wistar , Manguito Rotador/fisiopatologia , Traumatismos dos Tendões/fisiopatologia
7.
Gene Ther ; 21(7): 673-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24807807

RESUMO

Suicide gene therapy (SGT) is a promising strategy for treating cancer. In this work, we show that thymidine phosphorylase (TP) deficiency, the underlying genetic defect in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), presents an opportunity to apply SGT using capecitabine, a commonly used prodrug that is converted into 5-fluorouracil by TP. Using an immortalised B-lymphoblastoid cell line from a patient with MNGIE, the tumourigenic EL-4 cell line, lentiviral vectors encoding TP and a double knockout (Tymp(-/-)Upp1(-/-)) murine model, we found that EL-4 cell-derived TP(+) tumours were exquisitely sensitive to capecitabine and generated a significant local bystander effect. In addition, we detected a spontaneous cytolytic immune response in a significant fraction of the animals surviving more than 20 days after termination of the therapy. These data indicate that, in individuals lacking TP expression, TP is a highly specific suicide gene, which can be used to treat tumours that could hypothetically arise in MNGIE patients undergoing gene therapy, as these tumours will likely originate from the gene-modified cells and will be selectively targeted by capecitabine. These observations have important implications for gene therapy for MNGIE.


Assuntos
Genes Transgênicos Suicidas , Terapia Genética/métodos , Pseudo-Obstrução Intestinal/genética , Pseudo-Obstrução Intestinal/terapia , Lentivirus/genética , Encefalomiopatias Mitocondriais/genética , Encefalomiopatias Mitocondriais/terapia , Timidina Fosforilase/metabolismo , Animais , Capecitabina , Linhagem Celular Tumoral , Terapia Combinada , Desoxicitidina/análogos & derivados , Desoxicitidina/metabolismo , Desoxicitidina/uso terapêutico , Modelos Animais de Doenças , Fluoruracila/análogos & derivados , Fluoruracila/metabolismo , Fluoruracila/uso terapêutico , Técnicas de Inativação de Genes , Vetores Genéticos/administração & dosagem , Humanos , Pseudo-Obstrução Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Encefalomiopatias Mitocondriais/patologia , Distrofia Muscular Oculofaríngea , Oftalmoplegia/congênito , Timidina Fosforilase/genética
8.
Ann Oncol ; 25(12): 2433-2442, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25223485

RESUMO

BACKGROUND: Programmed cell death ligand 1 (PD-L1) is a cell surface molecule that plays a critical role in suppressing immune responses, mainly through binding of the PD-1 receptor on T lymphocytes. PD-L1 may be expressed by metastatic melanoma (MM). However, its clinical and biological significance remains unclear. Here, we investigated whether expression of PD-L1 in MM identifies a biologically more aggressive form of the disease, carrying prognostic relevance. PATIENTS AND METHODS: PD-L1 expression was analyzed by immunohistochemistry using two different antibodies in primary tumors and paired metastases from 81 melanoma patients treated at a single institution. Protein expression levels were correlated with PD-L1 mRNA, BRAF mutational status and clinical outcome. PD-L1(+) and PD-L1(-) subsets of the A375 cell line were stabilized in vitro and compared using gene expression profiling and functional assays. Results were confirmed using xenograft models. RESULTS: PD-L1 membrane positivity was detected in 30/81 (37%) of patients. By multivariate analysis, Breslow thickness and PD-L1 membrane positivity were independent risk factors for melanoma-specific death {PD-L1 5% cutoff [hazard ratio (HR) 3.92, confidence interval (CI) 95% 1.61-9.55 P < 0.003], PD-L1 as continuous variable (HR 1.03, 95% CI 1.02-1.04 P < 0.002)}. PD-L1 expression defined a subset of the BRAF-mutated A375 cell line characterized by a highly invasive phenotype and by enhanced ability to grow in xenograft models. CONCLUSIONS: PD-L1 is an independent prognostic marker in melanoma. If confirmed, our clinical and experimental data suggest that PD-L1(+) melanomas should be considered a disease subset with distinct genetic and morpho-phenotypic features, leading to enhanced aggressiveness and invasiveness.


Assuntos
Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/metabolismo , Melanoma/metabolismo , Humanos , Melanoma/genética , Melanoma/patologia , Invasividade Neoplásica , Metástase Neoplásica , Análise de Sobrevida
9.
J Biol Inorg Chem ; 19(4-5): 715-26, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24510295

RESUMO

The aim of this study is to describe the synthesis of, relaxometric characterization of, pharmacokinetic properties of, and animal imaging experiments with a new, low molecular weight gadolinium complex with high binding affinity toward serum albumin. The gadolinium(III) chelate (B25716/1) is based on the structure of the heptadentate ligand 1,4-bis(hydroxycarbonylmethyl)-6-[bis(hydroxycarbonylmethyl)]amino-6 methylperhydro-1,4-diazepine (AAZTA) covalently conjugated to an analogue of deoxycholic acid. The study was conducted as a comparison with that of an analogous complex based on the octadentate diethylenetriaminepentaacetic acid ligand B22956/1 (whose albumin binding properties were previously assessed). The structural modification with respect to B22956/1 leads to a system that can host two coordinated water molecules in fast exchange with bulk water with potential higher efficiency as an MRI contrast agent. On interaction with human serum albumin the expected-field-independent-relaxation enhancement is not observed, possibly as a consequence of the displacement of one of the two inner-sphere water molecules of the gadolinium complex. At clinically relevant magnetic fields, however, the plasma relaxivity of B25716/1 is markedly higher than that shown by B22956/1, owing to concomitant synergistic contributions from the electronic correlation time and water molecules in the second coordination sphere. The capability of B25716/1 to enhance tumor regions in magnetic resonance images was assessed in vivo at 3 T on a xenograft tumor mouse model prepared with PC-3 cells. B25716/1 displays signal enhancements approximately double those observed for B22956/1, in agreement with the findings of the in vitro relaxivity investigations.


Assuntos
Meios de Contraste/química , Gadolínio/química , Imageamento por Ressonância Magnética/métodos , Animais , Humanos , Masculino , Camundongos , Neoplasias da Próstata/diagnóstico
10.
Phys Chem Chem Phys ; 16(48): 27025-36, 2014 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-25382595

RESUMO

The temperature dependence of (1)H and (13)C nuclear spin-lattice relaxation rate 1/T1 has been studied in the 1.6-4.2 K temperature range in pure pyruvic acid and in pyruvic acid containing trityl radicals at a concentration of 15 mM. The temperature dependence of 1/T1 is found to follow a quadratic power law for both nuclei in the two samples. Remarkably the same temperature dependence is displayed also by the electron spin-lattice relaxation rate 1/T1e in the sample containing radicals. These results are explained by considering the effect of the structural dynamics on the relaxation rates in pyruvic acid. Dynamic nuclear polarization experiments show that below 4 K the (13)C build up rate scales with 1/T1e, in analogy to (13)C 1/T1 and consistently with a thermal mixing scenario where all the electrons are collectively involved in the dynamic nuclear polarization process and the nuclear spin reservoir is in good thermal contact with the electron spin system.

11.
Radiography (Lond) ; 30(4): 1080-1084, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38772064

RESUMO

INTRODUCTION: Exposure of iodinated contrast media (ICM) to X-rays is not uncommon, as contrast media are often stored in close proximity to radiological equipment. However, the interaction between X-rays and ICM is not widely investigated in literature. The present study aims to investigate the chemical stability of iomeprol and iopamidol, two commercial iodinated ICM commonly used in diagnostic imaging, under X-rays exposure. METHODS: Different formulations of iopamidol and iomeprol (iodine concentration 9 to 400 mgI/mL, volume 50-500 mL) were exposed to three different conditions of X-ray irradiation: i) 1 month storage in CT room (≈5-15 mGy); (ii) low-dose protocol (≈10 mGy); (ii) stressed protocol (≈100 mGy). Unexposed and exposed solutions were characterized by high-performance liquid chromatography in terms of concentration of active pharmaceutical ingredient (API), iodine species and by products. In addition, appearance and colour of the solutions were inspected and pH measured. RESULTS: API concentrations, appearance, colour and pH of the exposed formulations remained unaffected by X-rays. Measured concentrations of iodine species and by products were observed well within the acceptability criteria, i.e. values turned out to be lower than specifications limits established by the manufacturer, considering both release and shelf-life values. CONCLUSIONS: Up to 100 mGy X-ray exposure did not induce any alteration of iomeprol and iopamidol formulation, nor a detectable increase in the concentration of iodine species or by-products. IMPLICATIONS FOR PRACTICE: Our study strengthens the hypothesis that ICM are stable under X-rays exposure up to 100 mGy.


Assuntos
Meios de Contraste , Estabilidade de Medicamentos , Iopamidol , Iopamidol/análogos & derivados , Iopamidol/química , Raios X , Cromatografia Líquida de Alta Pressão , Humanos
12.
Br J Surg ; 100(10): 1349-56, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23939847

RESUMO

BACKGROUND: The management of portal vein (PV) involvement by pancreatic adenocarcinoma during pancreaticoduodenectomy (PD) is controversial. The aim of this study was to compare the outcomes of unplanned and planned PV resections as part of PD. METHODS: An analysis of PD over 11 years was performed. Patients who had undergone PV resection (PV-PD) were identified, and categorized into those who had undergone planned or unplanned resection. Postoperative and oncological outcomes were compared. RESULTS: Of 249 patients who underwent PD for pancreatic adenocarcinoma, 66 (26·5 per cent) had PV-PD, including 27 (41 per cent) planned and 39 (59 per cent) unplanned PV resections. Twenty-five of 27 planned PV resections were circumferential PV-PD, whereas 25 of 39 unplanned PV resections were partial PV-PD. Planned PV resections were performed in slightly younger patients (mean(s.d.) 60(9) versus 65(10) years; P = 0·031), and associated with longer operating times (mean(s.d.) 602(131) versus 458(83) min; P < 0·001) and more major complications (26 versus 5 per cent; P = 0·026). Planned PV resections were associated with a lower rate of positive margins (4 versus 44 per cent; P < 0·001) despite being carried out for larger tumours (mean(s.d.) 3·9(1·4) versus 2·9(1·0) cm; P = 0·002). There was no difference in survival between the two groups (P = 0·998). On multivariable analysis, margin status was a significant predictor of survival. CONCLUSION: Although planned PV resections for pancreatic adenocarcinoma were associated with higher rates of postoperative morbidity than unplanned resections, R0 resection rates were better.


Assuntos
Adenocarcinoma/cirurgia , Veias Mesentéricas/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/métodos , Veia Porta/cirurgia , Perda Sanguínea Cirúrgica , Implante de Prótese Vascular/métodos , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Duração da Cirurgia , Planejamento de Assistência ao Paciente , Veia Porta/lesões , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Neoplasias Vasculares/cirurgia
13.
J Am Chem Soc ; 134(36): 14982-90, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22894703

RESUMO

A robust, stable and processable family of mononuclear lanthanoid complexes based on polyoxometalates (POMs) that exhibit single-molecule magnetic behavior is described here. Preyssler polyanions of general formula [LnP(5)W(30)O(110)](12-) (Ln(3+) = Tb, Dy, Ho, Er, Tm, and Yb) have been characterized with static and dynamic magnetic measurements and heat capacity experiments. For the Dy and Ho derivatives, slow relaxation of the magnetization has been found. A simple interpretation of these properties is achieved by using crystal field theory.

14.
Phys Rev Lett ; 108(24): 247213, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23004325

RESUMO

We report ac susceptibility and continuous wave and pulsed EPR experiments performed on GdW10 and GdW30 polyoxometalate clusters, in which a Gd3+ ion is coordinated to different polyoxometalate moieties. Despite the isotropic character of gadolinium as a free ion, these molecules show slow magnetic relaxation at very low temperatures, characteristic of single molecule magnets. For T≲200 mK, the spin-lattice relaxation becomes dominated by pure quantum tunneling events, with rates that agree quantitatively with those predicted by the Prokof'ev and Stamp model [Phys. Rev. Lett. 80, 5794 (1998)]. The sign of the magnetic anisotropy, the energy level splittings, and the tunneling rates strongly depend on the molecular structure. We argue that GdW30 molecules are also promising spin qubits with a coherence figure of merit Q(M)≳50.

15.
Sci Rep ; 12(1): 5434, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361847

RESUMO

A significant amount of vascular thrombotic events are associated with rupture of the fibrous cap that overlie atherosclerotic plaques. Cap rupture is however difficult to predict due to the heterogenous composition of the plaque, unknown material properties, and the stochastic nature of the event. Here, we aim to create tissue engineered human fibrous cap models with a variable but controllable collagen composition, suitable for mechanical testing, to scrutinize the reciprocal relationships between composition and mechanical properties. Myofibroblasts were cultured in 1 × 1.5 cm-sized fibrin-based constrained gels for 21 days according to established (dynamic) culture protocols (i.e. static, intermittent or continuous loading) to vary collagen composition (e.g. amount, type and organization). At day 7, a soft 2 mm ∅ fibrin inclusion was introduced in the centre of each tissue to mimic the soft lipid core, simulating the heterogeneity of a plaque. Results demonstrate reproducible collagenous tissues, that mimic the bulk mechanical properties of human caps and vary in collagen composition due to the presence of a successfully integrated soft inclusion and the culture protocol applied. The models can be deployed to assess tissue mechanics, evolution and failure of fibrous caps or complex heterogeneous tissues in general.


Assuntos
Placa Aterosclerótica , Colágeno , Fibrose , Humanos
16.
Eur Rev Med Pharmacol Sci ; 26(6): 2000-2017, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35363351

RESUMO

Emergency or postoperative pain often represents an authentic challenge in patients who were already on opioid treatment for chronic pain. Thus, their management requires not only the physician's ability to treat acute pain, but also competence in switching the opioid that lost efficacy. Different aspects should be considered, such as opioids titration, switching, association and equianalgesia. The objective of this paper is to provide a narrative review, which has been elaborated and discussed among clinicians through an iterative process involving development and review of the draft during two web-based meetings and via email. This expert opinion aims to facilitate the correct opioid use through appropriate practices with a focus on pain treatment in emergency and postoperative pain. Equianalgesia tables were reviewed and integrated by clinicians and researchers with expertise in anesthesia, postoperative medicine, intensive care, emergency medicine pharmacology and addiction medicine. Special populations (liver/kidney failure, elder, pediatric, pregnancy/lactation) are discussed in detail along with other critical scenarios, such as: (i) rapid pain worsening in chronic pain (aggravating pain due to disease progression or tolerance development to analgesic therapy); (ii) acute pain on maintenance treatment; and (iii) pain management of complicated patients in emergency care. Extended and updated equianalgesia tables and conversion rates for 17 different opioid formulations (of 9 different molecules) are presented as follows. Opioids remain the class that best suits clinical needs of emergency and post-operative medicine. However, it should be stressed that equianalgesia can be affected by drug-to-drug interactions and pharmacological imprecision, in a complex field where clinical experience may be the main guiding principle.


Assuntos
Analgésicos Opioides , Dor Crônica , Idoso , Analgésicos , Analgésicos Opioides/efeitos adversos , Criança , Dor Crônica/tratamento farmacológico , Feminino , Humanos , Manejo da Dor , Dor Pós-Operatória/tratamento farmacológico , Gravidez
17.
Int J Immunopathol Pharmacol ; 24(2 Suppl): 37-43, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21781444

RESUMO

Formalin fixation under conditions that adversely affected the quality of the DNA, or indeterminant assay, or extensive tumor necrosis can compromise the genetic analysis of a brain bioptic sample. The success of DNA extraction and Methyl Guanine Methyl Transferase (MGMT) promoter methylation testing could be improved by freezing of fresh tumor tissue at the moment of biopsy. To ensure an increased concentration of the DNA samples the withdrawal should be performed in an area with high probability of neoplastic cells. From May 2007 to January 2011 fifty-two frameless neuronavigation brain needle biopsy were performed at the Neurosurgery Unit of the "Arcispedale Santa Maria Nuova" City Hospital of Reggio Emilia. The "image-guided" neuronavigated protocol sampling provided withdrawal specimens highly correlated with neuroimaging characteristics of the lesions. In this study the Authors report the genetic analysis on 24 cases of freezing fresh tissue from brain needle bioptic sample starting from July 2008. The molecular determination of MGMT promoter was assessed with the Nested-Methylation Specific-Polymerase Chain Reaction on fresh or cryopreserved needle bioptic tissue. The genetic characterization was feasible in all the bioptic samples. The MGMT promoter was methylated in eleven patients, including a brain infection. The diagnostic yield of brain biopsy could be increased by the neuronavigated trajectories and the intraoperative frozen sections. In the future the availability of the molecular-genetic characterization of a brain tumor before open surgery will provide important information for the optimal treatment. The MGMT promoter status analysis on needle bioptic fresh tissue could be available also for that patient not eligible for surgical remotion of the tumor.


Assuntos
Neoplasias Encefálicas/genética , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioma/genética , Regiões Promotoras Genéticas/genética , Proteínas Supressoras de Tumor/genética , Idoso , Biópsia por Agulha , Neoplasias Encefálicas/patologia , Feminino , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuronavegação
18.
Int J Immunopathol Pharmacol ; 24(2 Suppl): 45-50, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21781445

RESUMO

It is well known that primary and secondary glioblastomas are histologically largely indistinguishable. Therefore, the detection of IDH1 mutations or the status of the MGMT promoter on a simple bioptic sample could be one of major diagnostic and prognostic importance for glial patients that complements clinical criteria for distinguishing secondary from primary glioblastomas and to predict a more favourable prognosis. Currently, biopsy is the method of choice to obtain tissue from intracranial lesions with uncertain neurodiagnostic findings or in deep locations, with a minimal invasive approach. The needle biopsy with frameless neuronavigation could provide a sampling with elevated diagnostic yield and high concentration of DNA, due to the "image-guided" computer assisted technique of needle insertion through the most neurodiagnostic representative tumor area. The freezing of fresh tumor tissue at biopsy could greatly improve the success of DNA extraction. The concentration of the DNA samples can also improved from a withdrawal in an area with high probability of neoplastic cells. The present study reports the results of 17 patients who had undergone frameless image-guided intracranial needle biopsy from April 2008 until July 2010 at Neurosurgery Unit of the "Arcispedale Santa Maria Nuova" of Reggio Emilia. For these patients the molecular determination of MGMT promoter was assessed with the Nested-Methylation Specific-Polymerase Chain Reaction and the screening of mutations in IDH1 e IDH2 genes was performer by polymerase chain reaction (PCR) and direct sequencing on fresh or cryopreserved needle bioptic tissue.


Assuntos
Neoplasias Encefálicas/genética , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioma/genética , Isocitrato Desidrogenase/genética , Regiões Promotoras Genéticas/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Biópsia por Agulha , Neoplasias Encefálicas/patologia , Craniotomia , Feminino , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neuronavegação
19.
J Comput Chem ; 31(6): 1321-32, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20044799

RESUMO

We present a FORTRAN code based on a new powerful and efficient computational approach to solve the double exchange problem for high-nuclearity MV clusters containing arbitrary number of localized spins and itinerant electrons. We also report some examples in order to show the possibilities of the program.

20.
J Neurosurg Sci ; 54(2): 49-54, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21313955

RESUMO

In geometrical terms, tumor vascularity is an exemplary anatomical system that irregularly fills a three-dimensional Euclidean space. This physical characteristic, together with the highly variable vessel shapes and surfaces, leads to considerable spatial and temporal heterogeneity in the delivery of oxygen, nutrients and drugs, and the removal of metabolites. Although these biological features have now been well established, quantitative analyses of neovascularity in two-dimensional histological sections still fail to view tumor architecture in non-Euclidean terms, and this leads to errors in visually interpreting the same tumor, and discordant results from different laboratories. A review of the literature concerning the application of microvessel density (MVD) estimates, an Euclidean-based approach used to quantify vascularity in normal and neoplastic pituitary tissues, revealed some disagreements in the results and led us to discuss the limitations of the Euclidean quantification of vascularity. Consequently, we introduced fractal geometry as a better means of quantifying the microvasculature of normal pituitary glands and pituitary adenomas, and found that the use of the surface fractal dimension is more appropriate than MVD for analysing the vascular network of both. We propose extending the application of this model to the analysis of the angiogenesis and angioarchitecture of brain tumors.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Fractais , Microvasos/anatomia & histologia , Modelos Anatômicos , Neovascularização Patológica/patologia , Hipófise/irrigação sanguínea , Adenoma/irrigação sanguínea , Humanos , Neoplasias Hipofisárias/irrigação sanguínea
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