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1.
Sleep Breath ; 26(2): 879-885, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34302609

RESUMO

PURPOSE: Local and systemic inflammatory markers and pro-inflammatory cytokines are increased in children with obstructive sleep apnea syndrome (OSAS). Therefore, systemic or topical anti-inflammatory agents are used to treat this syndrome. We evaluated the treatment with systemic corticosteroids in children with severe OSAS and adenotonsillar hypertrophy before surgery. METHODS: This was an unblinded open label study. Children with severe OSAS (diagnosed through polysomnography, obstructive apnea-hypopnea index [AHI] > 10 eV/h) were recruited. Exclusion criteria included age < 3 years, history of acute or chronic cardiorespiratory or neuromuscular or metabolic disease; major craniofacial abnormalities; and chromosomal syndromes and epilepsy. Computer-generated random numbers were used for simple randomization of subjects. All children were treated with intranasal beclomethasone spray, and 15 children additionally received oral betamethasone and 0.1 mg/kg per day for 7 days. Sleep clinical record (SCR) and pulsoximetry were performed before and after 7 days in all children. RESULTS: Among 28 children with severe OSAS mean age was 4.5 ± 1.8 years, AHI 20.4 ± 1.8 eV/h). In children treated with intranasal and oral corticosteroids, mean (95.3 ± 1.1 vs 97.0 ± 0.8%, p = 0.0001) and minimum oxygen saturation (78.8 ± 6.3 vs 89.2 ± 4.2, p = 0.001) improved, and the SCR score (12.6 ± 1.2 vs 8.3 ± 1.1, p = 0.0001) was reduced. Children treated only with intranasal beclomethasone spray showed no differences in outcome measures before and after treatments. When we considered the oximetry measures, after corticosteroid treatment, we obtained statistical differences between the 2 groups (p < 0.01). CONCLUSIONS: These results seem to suggest that a short course of oral betamethasone could be useful to treat children with severe OSAS and adenotonsillar hypertrophy waiting for surgery.


Assuntos
Beclometasona , Apneia Obstrutiva do Sono , Beclometasona/uso terapêutico , Betametasona , Criança , Pré-Escolar , Humanos , Hipertrofia , Polissonografia , Apneia Obstrutiva do Sono/diagnóstico
2.
Chem Sci ; 8(8): 5526-5535, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28970932

RESUMO

A family of five [MIII2MII3] n+ trigonal bipyramidal cages (MIII = Fe, Cr and Al; MII = Co, Zn and Pd; n = 0 for 1-3 and n = 6 for 4-5) of formulae [Fe2Co3L6Cl6] (1), [Fe2Zn3L6Br6] (2), [Cr2Zn3L6Br6] (3), [Cr2Pd3L6(dppp)3](OTf)6 (4) and [Al2Pd3L6(dppp)3](OTf)6 (5) (where HL is 1-(4-pyridyl)butane-1,3-dione and dppp is 1,3-bis(diphenylphosphino)propane) are reported. Neutral cages 1-3 were synthesised using the tritopic [MIIIL3] metalloligand in combination with the salts CoIICl2 and ZnIIBr2, which both act as tetrahedral linkers. The assembly of the cis-protected [PdII(dppp)(OTf)2] with [MIIIL3] afforded the anionic cages 4-5 of general formula [MIII2PdII3](OTf)6. The metallic skeleton of all cages describes a trigonal bipyramid with the MIII ions occupying the two axial sites and the MII ions sitting in the three equatorial positions. Direct current (DC) magnetic susceptibility, magnetisation and heat capacity measurements on 1 reveal weak antiferromagnetic exchange between the FeIII and CoII ions. EPR spectroscopy demonstrates that the distortion imposed on the {MO6} coordination sphere of [MIIIL3] by complexation in the {MIII2MII3} supramolecules results in a small, but measurable, increase of the zero field splitting at MIII. Complete active space self-consistent field (CASSCF) calculations on the three unique CoII sites of 1 suggest DCo ≈ -14 cm-1 and E/D ≈ 0.1, consistent with the magnetothermal and spectroscopic data.

3.
Pediatr Pulmonol ; 52(5): 699-709, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28052557

RESUMO

Although adenotonsillectomy is the first line treatment for children with obstructive sleep apnea syndrome (0SAS),1 improvement in objectively documented outcomes is often inadequate and a substantial number of children have residual disease. Early recognition and treatment of children with persistent OSAS is required to prevent long-term morbidity. The management of these children is frequently complex and a multidisciplinary approach is required as most of them have additional risk factors for OSAS and comorbidities. In this paper, we first provide an overview of children at risk for persistent disease following adenotonsillectomy. Thereafter, we discuss different diagnostic modalities to evaluate the sites of persistent upper airway obstruction and the currently available treatment options. Pediatr Pulmonol. 2017;52:699-709. © 2016 Wiley Periodicals, Inc.


Assuntos
Adenoidectomia , Apneia Obstrutiva do Sono/cirurgia , Tonsilectomia , Criança , Pré-Escolar , Humanos , Fatores de Risco , Resultado do Tratamento
4.
Vet J ; 203(3): 342-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25599897

RESUMO

The clinical signs, magnetic resonance imaging (MRI) findings, treatment and follow-up in seven dogs with hydrated nucleus pulposus extrusion (HNPE) are reported. All dogs had tetraparesis or tetraplegia. T2-weighted MRI revealed extradural hyperintense homogeneous material compressing the cervical spinal cord. After conservative treatment (five dogs) or surgical decompression (two dogs), all dogs returned to ambulatory function within 1 month. Follow-up MRI in conservatively treated dogs revealed complete disappearance of the extruded material. Histopathological examination of surgical specimens confirmed that the retrieved material was extruded nucleus pulposus with evidence of early degeneration.


Assuntos
Vértebras Cervicais/patologia , Doenças do Cão/diagnóstico , Deslocamento do Disco Intervertebral/veterinária , Animais , Doenças do Cão/etiologia , Doenças do Cão/terapia , Cães , Feminino , Deslocamento do Disco Intervertebral/diagnóstico , Deslocamento do Disco Intervertebral/etiologia , Deslocamento do Disco Intervertebral/terapia , Imageamento por Ressonância Magnética/veterinária , Masculino , Prognóstico , Quadriplegia/diagnóstico , Quadriplegia/etiologia , Quadriplegia/terapia , Quadriplegia/veterinária , Resultado do Tratamento
5.
Dalton Trans ; 43(30): 11502-9, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24840855

RESUMO

Two new infinite coordination chain compounds [Gd(CH3CO2)3(dmf)]∞ (1) and {[Gd(HO(CH2)3CO2)3(H2O)]·H2O}∞ (2) have been obtained attempting to modify a prototype molecular cooler. The structures of both compounds as determined by single-crystal X-ray diffraction are reported, together with a detailed study of their magnetic and thermal properties, describing for both compounds a large magneto-caloric effect. The dominant ferromagnetic interaction present in 2 clearly favours this material at low applied magnetic fields, with respect to 1 that exhibits antiferromagnetic interactions. Magneto-structural correlations of the sign and strength of the magnetic interactions are derived for carboxylato-bridged Gd(III) systems.

6.
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.

7.
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.

8.
Phys Rev Lett ; 107(11): 117203, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-22026699

RESUMO

We show that a chemically engineered structural asymmetry in [Tb2] molecular clusters renders the two weakly coupled Tb3+ spin qubits magnetically inequivalent. The magnetic energy level spectrum of these molecules meets then all conditions needed to realize a universal CNOT quantum gate. A proposal to realize a SWAP gate within the same molecule is also discussed. Electronic paramagnetic resonance experiments confirm that CNOT and SWAP transitions are not forbidden.

9.
Dalton Trans ; 39(46): 11210-7, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-20976340

RESUMO

Two new azido-Co(II) complexes with pyrazine carboxylato ligands, [Co(N(3))(L)·H(2)O](n) (L = pyrazine-2-carboxylato) (1) and [CoNa(N(3))(2)(L)](n) (2), have been obtained by carefully tuning the Co(II):N(3)(-) ratio. Here we present the structural and magnetic characterization of these new species. Modulation of the coordination environment of Co(II) leads to a variation of the magnetic properties of the obtained compounds. Complex 1 exhibits ferromagnetically coupled [Co(2)] units that form the rungs of the ladder with a nearly negligible coupling between these units, while complex 2 is a 2D arrangement of 1D Co(II) single-chain magnets.

10.
J Phys Chem B ; 112(32): 9729-35, 2008 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-18646796

RESUMO

We study the magnetic properties of two new functionalized single-molecule magnets belonging to the Mn 6 family (general formula [Mn (III)6O2(R-sao)6(O2C-th)2L(4-6)], where R=H (1) or Et (2), HO2C-th=3-thiophene carboxylic acid, L=EtOH, H2O and saoH2 is salicylaldoxime) and their grafting on the Au(111) surface. Complex 1 exhibits spin ground-state S=4, as the result of ferromagnetic coupling between the two antiferromagnetic Mn (III) 3 triangles, while slight structural changes in complex 2, switch the dominant magnetic exchange interactions from anti- to ferromagnetic, enhancing the spin ground-state to S=12 and, consequently, the effective energy barrier for the relaxation of magnetization. Direct-current and alternating-current magnetic susceptibility measurements show that the functionalized complexes preserve the main magnetic properties of the corresponding not-functionalized Mn 6 clusters (i.e., total spin value and magnetic behavior as a function of temperature), though a reduction of the anisotropy barrier is observed in complex 2. For both complexes, the -O2C-th functionalization allows the direct grafting on Au(111) surface by liquid-phase deposition. X-ray photoemission spectroscopy demonstrates that the stoichiometry of the molecular cores is preserved after grafting. Scanning tunneling microscopy (STM) reveals a sub-monolayer distribution of isolated clusters with a slightly higher coverage for complex 1. The cluster stability in the STM images and the S-2p energy positions demonstrate, for both derivatives, the strength of the grafting with the gold surface.

11.
Phys Rev Lett ; 97(16): 167202, 2006 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-17155429

RESUMO

We report on the Fe17 high-spin molecular cluster and show that this system is an exemplification of nanostructured dipolar magnetism. Each Fe17 molecule, with spin S=35/2 and axial anisotropy as small as D approximately -0.02 K, is the magnetic unit that can be chemically arranged in different packing crystals while preserving both the spin ground state and anisotropy. For every configuration, molecular spins are correlated only by dipolar interactions. The ensuing interplay between dipolar energy and anisotropy gives rise to macroscopic behaviors ranging from superparamagnetism to long-range magnetic order at temperatures below 1 K.

12.
Phys Rev Lett ; 95(22): 227206, 2005 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-16384263

RESUMO

Time-dependent specific heat experiments on the molecular nanomagnet Fe8 and the isotopic enriched analogue 57Fe8 are presented. The inclusion of the 57Fe nuclear spins leads to a huge enhancement of the specific heat below 1 K, ascribed to a strong increase in the spin-lattice relaxation rate gamma arising from incoherent, nuclear-spin-mediated magnetic quantum tunneling (MQT) in the ground doublet. Since gamma is found comparable to the expected tunneling rate, the MQT process has to be inelastic. A model for the coupling of the tunneling spins to the lattice is presented. Under transverse field, a crossover from nuclear-spin-mediated to phonon-induced tunneling is observed.

13.
Phys Rev Lett ; 93(11): 117202, 2004 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-15447374

RESUMO

Can magnetic interactions between single-molecule magnets (SMMs) in a crystal establish long-range magnetic order at low temperatures deep in the quantum regime, where the only electron spin fluctuations are due to incoherent magnetic quantum tunneling (MQT)? Put inversely: can MQT provide the temperature dependent fluctuations needed to destroy the ordered state above some finite T(c), although it should basically itself be a T-independent process? Our experiments on two novel Mn4 SMMs provide a positive answer to the above, showing at the same time that MQT in the SMMs has to involve spin-lattice coupling at a relaxation rate equaling that predicted and observed recently for nuclear-spin-mediated quantum relaxation.

14.
Artigo em Inglês | MEDLINE | ID: mdl-9228320

RESUMO

Meniscal transplantation was performed in two groups of 15 adult goats each, using cryopreserved (group I) and deep-frozen (group II) allografts. Animals were killed at 2 weeks, 1, 3, 6 and 12 months, and a gross, histological and biochemical (water and glycosaminoglycan) evaluation of the menisci was performed. The allografts of both groups showed a normal gross appearance and had in most cases healed at the horn attachments and at the peripheral capsular tissue with a dense scar tissue and no signs of rejection. Histological analysis showed that at 2 weeks in group I the cell number was decreased compared with the controls, and the cells were mainly distributed in the superficial layers. In group II at 2 weeks, only a few cells were present at the peripheral attachment of the menisci. At 1 month in both groups, the cell repopulation can be seen extending from the peripheral area to the superficial layers. Cell proliferation and vascularization are particularly evident in both groups in the 3-month samples. At 6 months and 1 year the grafts can be seen to be completely remodelled and morphologically similar to normal menisci in both groups. Biochemical analysis showed in both groups an increase in water content and a progressive decrease in the concentration of glycosaminoglycans. At 1 year in both groups, there were moderate degenerative changes in the articular cartilage of the tibial plateau, which were more evident in the area of exposed cartilage than in that covered by the meniscus. These results suggest that there are no significant differences between the cryopreserved and deep-frozen grafts, and that even if cryopreservation makes it possible to maintain a partial cell viability in the tissue, this does not seem to improve the morphological and biochemical characteristics of the graft.


Assuntos
Meniscos Tibiais/transplante , Preservação de Tecido/métodos , Animais , Sobrevivência Celular , Criopreservação , Feminino , Glicosaminoglicanos/análise , Cabras , Membro Posterior/cirurgia , Meniscos Tibiais/química , Meniscos Tibiais/patologia , Transplante Homólogo
15.
Sci Total Environ ; 153(3): 211-7, 1994 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-7939622

RESUMO

The usefulness of factual health and safety databanks is discussed in this paper. Four databanks have been selected for this study: HSDB (Hazardous Substances Data Bank), ECDIN (Environmental Chemicals Data Information Network), RTECS (Registry of the Toxic Effects of Chemical Substances) and CCRIS (Chemical Carcinogenesis Research Information). The quality of the information available in the databanks considered was examined for five different chemical compounds and the completeness of the information available was carried out by an analysis of carcinogenic and mutagenic data.


Assuntos
Bases de Dados Factuais , Substâncias Perigosas/efeitos adversos , Animais , Carcinógenos , Bases de Dados Factuais/normas , Humanos , Mutagênicos/efeitos adversos , Toxicologia
16.
Clin Chim Acta ; 207(3): 205-13, 1992 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-1395027

RESUMO

A flow-through system for the determination of salicylate in blood is described. It consists of a Clark-type oxygen probe with the enzyme salicylate hydroxylase chemically bound to polymer supports. This probe, when inserted into a flow-through cell in the presence of salicylate, oxygen and NAD(P)H, produced a current signal proportional to the concentration of salicylate. Salicylate was assayed in the range 10 mumol/l up to 200 mumol/l with a detection limit of 3 mumol/l. Salicylate analysis was optimized by selecting the appropriate pH, buffer, temperature, enzyme immobilization and NAD(P)H concentration. The accuracy of this method was evaluated by recovery studies on 15 sera. Analysis of salicylate in serum sample was performed by diluting samples thirty fold with phosphate buffer to fit the calibration graphs. The response time of the probe was 2 min and 6 min was the time to perform a single analysis. Results compared with the TDx procedure correlated well.


Assuntos
Oxigênio/metabolismo , Salicilatos/sangue , Eletroquímica , Eletrodos , Enzimas Imobilizadas , Humanos , Concentração de Íons de Hidrogênio , Monitorização Fisiológica/métodos , Reprodutibilidade dos Testes , Ácido Salicílico , Temperatura
17.
Biosens Bioelectron ; 5(1): 27-35, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2178637

RESUMO

Serum cholinesterase activity and the dibucaine numbers have been determined by using a hydrogen peroxide electrode and the enzyme choline oxidase immobilized on a nylon net. The analysis procedure is extremely simple and very fast allowing 30 cholinesterase determinations per hour. Both cholinesterase activity and dibucaine number measurements could be performed in 5 min and by using serum samples of only 10 microliters. When used in sera the probe showed no interference from electroactive compounds present in blood, and also showed good stability and reproducibility. These features make this sensor appropriate for continuous extracorporeal circuit blood monitoring of succinylcholine during surgery.


Assuntos
Técnicas Biossensoriais , Colinesterases/sangue , Dibucaína/farmacologia , Oxirredutases do Álcool , Colina , Inibidores da Colinesterase , Enzimas Imobilizadas , Humanos , Peróxido de Hidrogênio
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