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1.
Phys Rev Lett ; 126(7): 071801, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666471

RESUMO

The MoEDAL trapping detector consists of approximately 800 kg of aluminum volumes. It was exposed during run 2 of the LHC program to 6.46 fb^{-1} of 13 TeV proton-proton collisions at the LHCb interaction point. Evidence for dyons (particles with electric and magnetic charge) captured in the trapping detector was sought by passing the aluminum volumes comprising the detector through a superconducting quantum interference device (SQUID) magnetometer. The presence of a trapped dyon would be signaled by a persistent current induced in the SQUID magnetometer. On the basis of a Drell-Yan production model, we exclude dyons with a magnetic charge ranging up to five Dirac charges (5g_{D}) and an electric charge up to 200 times the fundamental electric charge for mass limits in the range 870-3120 GeV and also monopoles with magnetic charge up to and including 5g_{D} with mass limits in the range 870-2040 GeV.

2.
Phys Rev Lett ; 123(2): 021802, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386510

RESUMO

MoEDAL is designed to identify new physics in the form of stable or pseudostable highly ionizing particles produced in high-energy Large Hadron Collider (LHC) collisions. Here we update our previous search for magnetic monopoles in Run 2 using the full trapping detector with almost four times more material and almost twice more integrated luminosity. For the first time at the LHC, the data were interpreted in terms of photon-fusion monopole direct production in addition to the Drell-Yan-like mechanism. The MoEDAL trapping detector, consisting of 794 kg of aluminum samples installed in the forward and lateral regions, was exposed to 4.0 fb^{-1} of 13 TeV proton-proton collisions at the LHCb interaction point and analyzed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges equal to or above the Dirac charge are excluded in all samples. Monopole spins 0, ½, and 1 are considered and both velocity-independent and-dependent couplings are assumed. This search provides the best current laboratory constraints for monopoles with magnetic charges ranging from two to five times the Dirac charge.

3.
J Dairy Sci ; 102(8): 6790-6801, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31178182

RESUMO

This study proposed the General Health Index of Cheese (GHIC) as an indicator for the presence of health-promoting compounds in cheese and compared the antioxidant capacity and phenolic and fatty acid contents of cheeses from goats consuming 7 forage species. Ninety-one homogeneous Red Syrian goats were randomly assigned to 1 of 7 feeding treatments (Festuca arundinacea, Hordeum vulgare, Triticosecale, Pisum sativum, Trifolium alexandrinum, Vicia sativa, and Vicia faba minor). The housed goat groups received the scheduled forage ad libitum. Forage species affected the antioxidant capacity, the phenolic and fatty acid contents, the Health Promoting Index, and the GHIC. Trifolium alexandrinum, Triticosecale, and Hordeum vulgare showed a clear advantage in terms of beneficial fatty acids content in goat cheese. Cheese from the Triticosecale group also showed a high antioxidant capacity value even if its polyphenol content was intermediate compared with others. Trifolium alexandrinum and Triticosecale had the highest value of the new index GHIC. This comparison suggests that there are important differences in fatty acid profile and polyphenol content among cheeses from goats fed grasses and legumes commonly used in the Mediterranean area. In this first approach, GHIC index, which combines the positive components found in cheese, seems to be a useful tool to provide an indication concerning the general health value of the product.


Assuntos
Ração Animal , Queijo/análise , Cabras/metabolismo , Animais , Antioxidantes/análise , Ácidos Graxos/análise , Festuca , Hordeum , Hidroxibenzoatos/análise , Leite/química , Pisum sativum , Polifenóis , Trifolium , Triticale , Vicia
4.
Vet Immunol Immunopathol ; 211: 38-43, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31084892

RESUMO

Natural antibodies (NAb) are antibodies that can bind to a particular antigen without any apparent antigenic stimulation. In this paper, a careful analysis has been carried out on NAb levels in goat kid serum; possible correlations with the total immunoglobulin (tot-Ig) levels and specific antibody (SpAb) response were considered. Twenty randomly chosen kids were submitted to a first blood sampling (day 0). After 60 and 100 days, new blood samplings were carried out in the same animals. On day 0, after blood collection, all animals were immunized with a commercial vaccine; the immunization was repeated 30 days apart. Some exogenous antigens were tested to verify their immunoreactivity to NAb. Among them, the synthetic hapten 2,4,6-trinitrophenyl (TNP) conjugated with bovine serum albumin, resulted as the antigen with the higher immunoreactivity to NAb. Tot-Ig levels increased over time (p < 0.001). On the contrary, NAb levels, both IgG- and IgM-isotypes, significantly decreased during the experimental period (p < 0.001 and <0.05, respectively). Linear regression analyses showed a high correlation between IgM-NAb and tot-IgM levels (p < 0.001) at all the evaluated sampling times. However, a significant correlation between IgG-NAb and IgM-NAb was found only at the 1st (p < 0.01) and at the 2nd sampling (p < 0.05). No significant correlations were found between SpAb response and the other assessed humoral immune parameters. The obtained results are discussed in the light of the possible use of NAb assessment for the evaluation of the immune system activity in goat.


Assuntos
Imunidade Adaptativa/imunologia , Anticorpos/imunologia , Cabras/imunologia , Imunoglobulinas/imunologia , Animais , Anticorpos/sangue , Formação de Anticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Cabras/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Imunoglobulinas/sangue , Masculino
5.
Phys Rev Lett ; 118(6): 061801, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28234515

RESUMO

MoEDAL is designed to identify new physics in the form of long-lived highly ionizing particles produced in high-energy LHC collisions. Its arrays of plastic nuclear-track detectors and aluminium trapping volumes provide two independent passive detection techniques. We present here the results of a first search for magnetic monopole production in 13 TeV proton-proton collisions using the trapping technique, extending a previous publication with 8 TeV data during LHC Run 1. A total of 222 kg of MoEDAL trapping detector samples was exposed in the forward region and analyzed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges exceeding half the Dirac charge are excluded in all samples and limits are placed for the first time on the production of magnetic monopoles in 13 TeV pp collisions. The search probes mass ranges previously inaccessible to collider experiments for up to five times the Dirac charge.

6.
Int J Oral Maxillofac Surg ; 46(3): 373-378, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27746008

RESUMO

The onset of delayed infection after lower third molar germectomy is influenced by the amount of distal space. This retrospective study aimed to determine whether the incidence of delayed onset infection is related to the space distal to the second molar. The ratio between the distal space and the crown width, measured according to the Ganss protocol on panoramic radiographs, was obtained for 218 surgical germectomies performed for orthodontic reasons in 134 patients. A delayed onset infection occurred following 20 germectomies at between 2 and 8 weeks after surgery; purulent exudates from the alveolus and swelling were present. In 16 of the 20 cases of infection, a Ganss ratio of <0.5 showed the almost complete absence of space distal to the second molar. This study found that the distal space was significantly and inversely correlated with delayed onset infection (P=0.004). From a clinical point of view, it is important for the surgeon to be aware that a higher Ganss ratio may indicate that a delayed onset infection is less likely to occur and that a lower Ganss ratio could indicate a greater likelihood of this type of infection, so that the patient can be properly informed.


Assuntos
Dente Serotino/cirurgia , Infecção da Ferida Cirúrgica/epidemiologia , Extração Dentária , Adolescente , Criança , Feminino , Humanos , Incidência , Masculino , Radiografia Panorâmica , Estudos Retrospectivos , Fatores de Risco , Infecção da Ferida Cirúrgica/diagnóstico por imagem , Adulto Jovem
7.
Andrology ; 5(1): 133-145, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27769103

RESUMO

Owing to the progressive decline of sperm motility during storage there is a need to find substances capable of enhancing sperm energy metabolism and motility and/or preserving it from oxidative damage. The aim of this study was to evaluate in frozen/thawed bovine spermatozoa the effect of several compounds, such as myo-inositol, pentoxifylline, penicillamine + hypotaurine + epinephrine mixture (PHE), caffeine and coenzyme Q10+ zinc + d-aspartate mixture (CZA), on either kinetic or metabolic parameters. Sperm kinetics was evaluated by Sperm Class Analyser whereas specific fluorochromes were used to evaluated mitochondrial membrane potential (MMP), intracellular pH, intracellular calcium concentration and lipid peroxidation. Lipid peroxidation was also evaluated by TBARS analysis. Treatments significantly affected total and progressive motility with different dynamics in relation to the incubation time. After the first hour of incubation, CZA treatment produced the best performance in total and progressive sperm motility as well as in curvilinear velocity, average path velocity and amplitude of head displacement, whereas pentoxifylline stimulated the highest straight-line velocity. MMP showed higher values (p < 0.01) after treatment with pentoxifylline and PHE. Intracytoplasmic calcium concentration and lipid peroxidation were significantly (p < 0.05) affected by the incubation time rather than the treatments. Intracellular pH varied significantly (p < 0.01) in relation to either the incubation time or treatments. In particular, it showed a progressive increase throughout incubation with values in control group significantly higher than in myo-inositol, PHE, caffeine, pentoxifylline and CZA groups (7.37 ± 0.03 vs. 7.29 ± 0.03, 7.28 ± 0.03, 7.26 ± 0.03, 7.22 ± 0.03 and 7.00 ± 0.03, respectively; p < 0.01).; however, among treatments, CZA displayed the lowest values. Significant correlations were found between sperm kinetic and metabolic parameters. These findings provide new comparative information on the effects of putative metabolic enhancers on kinetics and metabolic activities of bovine spermatozoa. In this study, a rapid methodological approach for evaluating sperm quality is proposed.


Assuntos
Cálcio/metabolismo , Peroxidação de Lipídeos/fisiologia , Potencial da Membrana Mitocondrial/fisiologia , Espermatozoides/metabolismo , Animais , Bovinos , Epinefrina/farmacologia , Concentração de Íons de Hidrogênio , Inositol/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Penicilamina/farmacologia , Pentoxifilina/farmacologia , Análise do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos , Taurina/análogos & derivados , Taurina/farmacologia , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia
8.
Clin Neurol Neurosurg ; 141: 43-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26731463

RESUMO

OBJECTIVES: To evaluate the efficacy and safety of Gamma Knife Radiosurgery (GKRS) in the treatment of single and multiple brain metastases. PATIENTS AND METHODS: From October 2012 to June 2014 106 patients were treated with Radiosurgery (RS) for brain metastases at University of Florence. 77 out of 106 patients had a radiological follow up and their data were analyzed. The target was defined as the enhancing lesion. The prescription dose was defined depending on tumor volume and tumor location. Each patient performed an MRI one month after GKRS for the first three months and every 3 months thereafter. Overall survival was calculated from the day of RS until death. Local recurrence (LR) was defined as radiologic growth of the irradiated lesion, while distant brain recurrence (DBR) was the evidence of brain lesion outside the previous irradiated field. Both the LR and DBR were calculated from the RS till the day of radiological evidence of relapse. The correlations within patient and disease characteristics and the outcomes of survival and disease control were analyzed. RESULTS: Mean follow up was 7.2 ± 4.8 months (range: 2.4-22.8 months). At the time of analysis 21 patients (27.3%) were dead. The overall survival (OS) at 1 year was 74%. On univariate Cox Regression analysis female gender (p=0.043, HR: 0.391, 95% CI: 0.157-0.972) and age >65 years (p=0.003 HR: 4.623, 95% CI: 1.687-12.663) were predictive for survival. On multivariate analysis, age older than 65 years (p=0.005HR: 4.254, 95% CI: 1.544-11.721) was confirmed as associated with worsened overall survival. 19 patients (24.7%) had recurrence in the radiosurgery field. The median time to local failure was 4.8 ± 2.0 months (range: 1.8-9.4 months) from GKRS. On Cox Regression univariate analysis, the only factor associated with higher risk of local failure was a number of treated lesions more than 4 (p=0.015, HR: 3.813, 95% CI: 1.298-11.202), no significant parameters were found at the multivariate analysis. The median time to develop distant brain failure was 6 ± 4.32 months (range: 1.08-21.6 months). Median distant brain control was 74% at 1 year. None of the factors analyzed was statistically significant for the distant brain relapse. The radiosurgery treatment was well tolerated. One patient treated for seven metastases developed seizures 8h after GKRS, he was treated with steroids and anticonvulsants. One patient had radiologic evidence of radionecrosis without any neurological symptoms. CONCLUSIONS: In well-performing patients with stable systemic disease radiosurgery can be performed as an exclusive treatment for brain metastases. Younger patients could have a greater benefit from the RS, on the other hand our finding confirm no correlation between the survival outcome and the number of lesions treated.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirurgia , Gerenciamento Clínico , Radiocirurgia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
J Dairy Sci ; 98(1): 37-46, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25465629

RESUMO

Twelve milking Girgentana goats were allocated into 3 groups and fed 3 diets ad libitum in a 3×3 Latin square design with 3 periods. The diets were Sulla fresh forage ad libitum (SUL), Sulla fresh forage ad libitum and 800g/d of barley meal (SULB), and mixed hay ad libitum and 800g/d of barley meal (HB). Changes were observed in total polyphenol intake, plasma oxidative status, plasma polyphenol content, metabolic status, milk polyphenol content, and total antioxidant capacity. The fresh forage diets (SUL and SULB) increased dry matter, total polyphenol, nontannic polyphenol and tannin intakes, and the milk total protein, casein, milk total polyphenols, and milk free polyphenols compared with the HB diet. The intake of condensed tannins was higher in the SUL than in the HB group, and an intermediate value was recorded for the SULB group. Plasma from the SUL- and SULB-fed goats exhibited greater total antioxidant capacity and greater total polyphenol and free polyphenol levels compared with the plasma from the HB group. Positive correlations between plasma total antioxidant capacity and condensed tannins intake (r=0.43), plasma total polyphenol and total polyphenol intake (r=0.61), and plasma free polyphenol and milk total polyphenols (r=0.38) were observed. The correlation between milk free polyphenols and whey total antioxidant capacity (r=0.42) highlights the role of free polyphenols in the determination of the antioxidant activity of milk. These results indicate that Sulla fresh forage exerts an antioxidant activity due to its secondary compounds that provide additional antioxidant value and that Sulla forage appears to be a promising strategy for improving product quality.


Assuntos
Ração Animal , Antioxidantes/análise , Fabaceae , Cabras/metabolismo , Leite/química , Polifenóis/análise , Ração Animal/análise , Animais , Dieta/veterinária , Metabolismo Energético , Feminino , Hordeum , Lactação/efeitos dos fármacos , Proteínas do Leite/análise , Polifenóis/administração & dosagem , Polifenóis/sangue , Taninos/administração & dosagem
10.
Eur J Surg Oncol ; 40(3): 277-81, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24388742

RESUMO

BACKGROUND: The dislocation of the malignant cells along the needle tract during breast cancer (BC) diagnosis has been demonstrated by several studies. However, the published experiences that relate the diagnostic technique with sentinel node (SN) involvement are few and controversial. The aim of our analysis was to evaluate the impact of different techniques for preoperative BC biopsy among prognostic factors of metastases occurrence in SN. MATERIALS AND METHODS: We reviewed the institutional clinical database of our Center. A total of 674 patients were diagnosed between February 1999 and December 2006 with invasive BC. SN metastases classification followed the 2002 American Joint Committee on Cancer (AJCC) TNM pathological staging: macrometastases, micrometastases, isolated tumor cells or negative. Only macrometastases and micrometastases were considered positive. Concerning fine-needle aspiration cytology, we used disposable needles of the size of 21-27 G. For percutaneous biopsy we used cutting needle type "tru-cut"; the Gauge needle ranged between 14 and 20. RESULTS: At univariate analysis of specific parameters using positive SN as outcome, percutaneous diagnostic technique did not affect significantly the SN positivity (p = 0.60). At multivariate models only central quadrant lesion (p = 0.005) and lymph vascular invasion (LVI) presence (p < 0.0001) maintained the statistical significance as risk factor for positive SN status. Polytomic logistics models showed that only LVI maintained the statistical significance both for prediction of micrometastases and macrometastases. CONCLUSIONS: Our analysis showed that different techniques used for BC diagnosis did not influence SN status.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/secundário , Micrometástase de Neoplasia/patologia , Inoculação de Neoplasia , Biópsia de Linfonodo Sentinela/efeitos adversos , Biópsia de Linfonodo Sentinela/métodos , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biópsia por Agulha Fina/efeitos adversos , Biópsia por Agulha Fina/métodos , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/cirurgia , Distribuição de Qui-Quadrado , Estudos de Coortes , Bases de Dados Factuais , Equipamentos Descartáveis , Feminino , Humanos , Imuno-Histoquímica , Incidência , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Células Neoplásicas Circulantes/patologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida
11.
Artigo em Inglês | MEDLINE | ID: mdl-24110064

RESUMO

Cardiac output (CO) monitoring is important in the hemodynamic management of critically ill patients. In a previous study, a novel non-invasive technique for CO monitoring based on prolonged expiration was proposed. The novel method showed good agreement with thermodilution on stable mechanically ventilated patients; unstable patients were excluded. The aim of this study is to improve the outcome of the above mentioned method on hemodynamic unstable patients, requiring vasoactive medications, and showing marked cardiogenic oscillations on waveforms related to expired gases. This prospective study has been carried out on three cardiac surgery patients; eighteen CO measurements were performed on each patient, and these values were compared with data obtained by thermodilution. The designed and tested algorithm allowed to reach a good agreement between CO measured by our method and by thermodilution (e.g., the mean percentage differences were 4%, 11% and 3%). Even though further validation is necessary, the results are quite promising and the adopted solution appears to allow the suitability of the prolonged expiration method also on unstable patients.


Assuntos
Débito Cardíaco , Algoritmos , Procedimentos Cirúrgicos Cardíacos , Expiração , Cardiopatias/fisiopatologia , Cardiopatias/cirurgia , Hemodinâmica , Humanos , Monitorização Fisiológica/métodos , Estudos Prospectivos , Respiração Artificial , Termodiluição
13.
Minerva Anestesiol ; 79(5): 515-24, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23419341

RESUMO

BACKGROUND: Forces applied on oropharyngeal soft tissues by direct laryngoscopy may cause damage to the patients. The aim of this study was to measure the forces applied during the manoeuvres to achieve glottis visualization and tracheal intubation, comparing direct laryngoscopy and videolaryngoscopy in vivo. METHODS: Thirty adult patients (ASA physical status 1 or 2, BMI between 18 and 30 kg/m2, no difficulty to intubate) were randomly and blindly assigned to one of two groups. Forces and pressure distribution applied during glottis visualization and intubation were measured using film pressure transducers, comparing Macintosh direct laryngoscope and GlideScope videolaryngoscope. RESULTS: Fifteen patients from each group, all with Cormack-Lehane grade 1 view, were analyzed. Forces applied during the intubation with the GlideScope were significantly lower than forces applied with the Macintosh (8+4 N vs. 40+14 N, respectively, P<0.001). Considering the Macintosh laryngoscope, the minimal force applied for glottis visualization was significantly lower than the one applied for intubation (16+6 N vs. 40+14 N, respectively, P<0.005). When using the Macintosh laryngoscope, forces were concentrated mostly on the tip, whereas with the GlideScope forces' concentration in a particular area was not observed. CONCLUSION: Our study shows that in patients with normal airways the GlideScope allows a view of glottis and permits a successful tracheal intubation applying lower force (significantly in intubation) as compared to the Macintosh laryngoscope. Also, the GlideScope probe distributes the forces more homogeneously to the tissue thus further reducing the potential for tissue damage.


Assuntos
Laringoscópios , Laringoscopia , Orofaringe/lesões , Orofaringe/fisiologia , Adolescente , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Intubação Intratraqueal/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pressão , Adulto Jovem
14.
Gene Ther ; 20(3): 274-82, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22551778

RESUMO

Duchenne muscular dystrophy (DMD) cardiomyopathy patients currently have no therapeutic options. We evaluated catheter-based transendocardial delivery of a recombinant adeno-associated virus (rAAV) expressing a small nuclear U7 RNA (U7smOPT) complementary to specific cis-acting splicing signals. Eliminating specific exons restores the open reading frame resulting in translation of truncated dystrophin protein. To test this approach in a clinically relevant DMD model, golden retriever muscular dystrophy (GRMD) dogs received serotype 6 rAAV-U7smOPT via the intracoronary or transendocardial route. Transendocardial injections were administered with an injection-tipped catheter and fluoroscopic guidance using X-ray fused with magnetic resonance imaging (XFM) roadmaps. Three months after treatment, tissues were analyzed for DNA, RNA, dystrophin protein, and histology. Whereas intracoronary delivery did not result in effective transduction, transendocardial injections, XFM guidance, enabled 30±10 non-overlapping injections per animal. Vector DNA was detectable in all samples tested and ranged from <1 to >3000 vector genome copies per cell. RNA analysis, western blot analysis, and immunohistology demonstrated extensive expression of skipped RNA and dystrophin protein in the treated myocardium. Left ventricular function remained unchanged over a 3-month follow-up. These results demonstrated that effective transendocardial delivery of rAAV-U7smOPT was achieved using XFM. This approach restores an open reading frame for dystrophin in affected dogs and has potential clinical utility.


Assuntos
Dependovirus/genética , Distrofina/genética , Imageamento por Ressonância Magnética/métodos , Distrofia Muscular de Duchenne/terapia , RNA Nuclear Pequeno/genética , Transdução Genética/métodos , Animais , Sequência de Bases , Western Blotting , Modelos Animais de Doenças , Cães , Distrofina/metabolismo , Éxons/genética , Feminino , Expressão Gênica , Terapia Genética/métodos , Vetores Genéticos/genética , Humanos , Imuno-Histoquímica , Masculino , Dados de Sequência Molecular , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Miocárdio/metabolismo , RNA Nuclear Pequeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Sf9
15.
Br J Anaesth ; 108(1): 146-51, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21965048

RESUMO

BACKGROUND: The forces applied to the soft tissues of the upper airway may have a deleterious effect. This study was designed to evaluate the performance of the GlideScope compared with the Macintosh laryngoscope. METHODS: Twenty anaesthetists and 20 trainees attempted tracheal intubation of a Laerdal SimMan manikin. Forces and pressure distribution applied by both laryngoscope blades onto the soft upper airway tissues were measured using film pressure transducers. The minimal force needed to achieve a successful intubation, in the same simulated scenario, was measured; additionally, we considered the visualization score achieved by using the Cormack-Lehane grades. RESULTS: All participants applied, on average, lower force with the GlideScope than with the Macintosh in each simulated scenario. Forces [mean (sd)] applied in the normal airway scenario [anaesthetists: Macintosh 39 (22) N and GlideScope 27 (15) N; trainees: Macintosh 45 (24) N and GlideScope 21 (15) N] were lower than forces applied in the difficult airway scenario [anaesthetists: Macintosh 95 (22) N and GlideScope 66 (20) N; trainees: Macintosh 100 (38) N and GlideScope 48 (16) N]. All the intubations using the GlideScope were successful, regardless of the scenario and previous intubation experience. The average pressure on the blades was 0.13 MPa for the Macintosh and 0.07 MPa for the GlideScope, showing a higher uniformity for the latter. CONCLUSIONS: The GlideScope allowed the participants to obtain a successful intubation applying a lower force. A flatter and more uniform pressure distribution, a higher successful rate, and a better glottic view were observed with the GlideScope.


Assuntos
Laringoscópios/efeitos adversos , Laringoscopia/efeitos adversos , Laringoscopia/métodos , Manequins , Análise de Variância , Interpretação Estatística de Dados , Desenho de Equipamento , Glote/anatomia & histologia , Humanos , Laringoscopia/educação , Pressão , Transdutores de Pressão
16.
Artigo em Inglês | MEDLINE | ID: mdl-23366484

RESUMO

A non-invasive method to estimate cardiac output (CO) in mechanically ventilated patients, based on prolonged expiration, has been previously described. With the aim to assess its performances, we prospectively enrolled fifteen cardiac surgery patients, and compared the results obtained with the non-invasive method with the ones obtained using two invasive approaches based on thermodilution. The correlations between the prolonged expiration method with both the thermodilution-based ones show high values (ρ(2)>0.77 and ρ(2)>0.89). This encouraging agreement is also confirmed by the closeness between the measured values of CO: the mean differences considering all patients and the two reference invasive techniques are -0.8 % and -7.5 %. These values show the slight underestimation of CO by the proposed non-invasive method with respect to the gold standard. On the other hand the described method could represent a good compromise between accuracy and non-invasiveness, which fosters the implementation of a new monitoring tool suitable for a semi-continuous CO assessment.


Assuntos
Débito Cardíaco/fisiologia , Respiração Artificial , Termodiluição/métodos , Algoritmos , Humanos
17.
Artigo em Inglês | MEDLINE | ID: mdl-22254542

RESUMO

With the aim to assess metabolic monitor's suitability to the use in mechanically ventilated patients, a method, based on the comparison between the measurements performed by the monitor and the ventilator, is here described. In particular, the effects of positive end-expiratory pressure and oxygen inspiratory fraction (FiO(2)) on the metabolic measurements in presence of bias flow are investigated. In this study a metabolic monitor is used to estimate the energy expenditure of 10 mechanically ventilated cardiosurgical patients at different positive end-expiratory pressure, FiO(2) and two different modes of ventilation, with bias flow. The influence of the ventilatory settings on the parameters measured by the monitor is here quantified: a slight decrease of respiratory quotient and a slight increase of resting energy expenditure are observed with the increase of FiO(2). This study shows a good agreement between the measurements of the two devices: FiO(2), expiratory volume (mean difference lower than 3%), and respiratory frequency (mean difference lower than 1%). This also demonstrates the capability of the metabolic monitor to reject the effect of the bias flow.


Assuntos
Testes Respiratórios/instrumentação , Calorimetria/instrumentação , Diagnóstico por Computador/métodos , Pulmão/fisiologia , Consumo de Oxigênio/fisiologia , Respiração com Pressão Positiva/instrumentação , Mecânica Respiratória/fisiologia , Calorimetria/métodos , Desenho Assistido por Computador , Diagnóstico por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Respiração com Pressão Positiva/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Artigo em Inglês | MEDLINE | ID: mdl-21096120

RESUMO

Proportional strategies for artificial ventilation are the most recent form of synchronized partial ventilatory assistance and intra-breath control techniques available in clinical practice. Currently, the majority of commercial ventilators allowing proportional ventilation uses proportional valves to generate the flow rate pattern. This paper proposes on-off solenoid valves for proportional ventilation given their small size, low cost and short switching time, useful for supplying high frequency ventilation. A new system based on a novel fast switching driver circuit combined with on/off solenoid valve is developed. The average short response time typical of onoff solenoid valves was further reduced through the driving circuit for the implementation of PWM control. Experimental trials were conducted for identifying the dynamic response of the PWM driven on/off valve and for verifying its effectiveness in generating variable-shaped ventilatory flow rate patterns. The system was able to smoothly follow the reference flow rate patterns also changing in time intervals as short as 20 ms, achieving a flow rate resolution up to 1 L/min and repeatability in the order of 0.5 L/min. Preliminary results showed the feasibility of developing a stand alone portable device able to generate both proportional and high frequency ventilation by only using on-off solenoid valves.


Assuntos
Biorretroalimentação Psicológica/instrumentação , Magnetismo/instrumentação , Respiração Artificial/instrumentação , Mecânica Respiratória , Processamento de Sinais Assistido por Computador/instrumentação , Terapia Assistida por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos
19.
Artigo em Inglês | MEDLINE | ID: mdl-21096165

RESUMO

The aim of this study is to evaluate the Pulmonary Rehabilitation (PR) and post-operative complications on lung cancer patients by means of opto-electronic plethysmography (OEP). FEV1 and FVC have been measured through OEP on 13 lung cancer patients, before and after lobectomy and after pulmonary rehabilitation (PR). In every patient, FEV1 decreases after surgery, whereas FVC decreases only in 8 patients. Mean FEV1 and FVC decrease in every compartment of chest wall (CW) and in CW after lobectomy and improve in post-rehabilitation phase (ΔFEV1(CW)=+31%; ΔFVC(CW) = +13%). The highest positive variation of FEV1 has been measured in rib-cage abdominal compartment (ΔFEV1(RCa) =+59%) and of FVC in abdomen (ΔFVC(AB) = +24%), after PR.


Assuntos
Neoplasias Pulmonares/reabilitação , Pletismografia/métodos , Biofísica/métodos , Desenho de Equipamento , Exercício Físico , Feminino , Volume Expiratório Forçado , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Óptica e Fotônica , Pletismografia/instrumentação , Testes de Função Respiratória , Fenômenos Fisiológicos Respiratórios , Parede Torácica/patologia , Resultado do Tratamento , Capacidade Vital
20.
Artigo em Inglês | MEDLINE | ID: mdl-19964742

RESUMO

A theoretical analysis of the forces acting on the laryngoscope during the lifting of the epiglottis is carried out by applying the basic principles of statics. The static model of a laryngoscope equipped with a straight and a curved blade and the forces variation, as a function of the introduction angle and of tissue reaction application point, are described. The pharyngeal tissues and epiglottis pressure distribution on the blade is obtained, with a 1mm(2) resolution, by measurements performed in-vitro on a simulation mannequin, using straight and curved blades. The straight blade requires more effort than the curved one to obtain the same visualization of vocal cords, however forces exerted by using a laryngoscope with a curved blade do not vary linearly with the application point of tissue reaction. Average intensity of the tissue reaction has been found in the order of 32+/-11 N. Pressure distribution is maximally concentrated on the tip of curved blades (0.5 MPa on 5mm axial length), whereas it is more dispersed on straight blades (0.2 MPa on 10mm axial length). The inclination of the handle also influences the effort of the operator: for both blades, from 0 rad to 1.57 rad, the lifting force shows a total variation of about 13% of the top value, the transversal forces vary less than 6% of the top value.


Assuntos
Epiglote/fisiologia , Laringoscópios , Laringe/fisiologia , Modelos Biológicos , Simulação por Computador , Módulo de Elasticidade/fisiologia , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Pressão , Estresse Mecânico
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