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1.
Bone Marrow Transplant ; 59(6): 874-879, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38472408

RESUMO

Advanced stage (IIB-IVB) Mycosis Fungoides (MF) and Sezary Syndrome (SS) have a poor prognosis with median survival <5 years. We report long-term outcomes of a non-myeloablative allogeneic stem cell transplantation regimen consisting of total skin electron beam therapy, total lymphoid irradiation and antithymocyte globulin. Our prospective cohort consisted of 41 patients with a higher proportion of MF (34MF, 7SS). Acute GVHD Grade 2 to 4 was seen in 31.7% and chronic GVHD Grade 2 to 4 in 24%. The cumulative incidence of non-relapse mortality was 9.8% at 1 year and 12.6% at 2 years. At Day +90 post-transplant 66% of patients had a complete response (CR). With a median post-transplant follow up of 5.27 years, the 5-year overall survival rate was 37.7% (MF 36.7%, SS 57.1%). The 5-year cumulative incidence of progressive disease or relapse was 52.7% in all patients but only 20.8% in those with CR at transplant compared to 70.6% in those not in CR at transplant (p = 0.006). Long term survival is possible in advanced MF and SS with non-myeloablative transplantation and outcomes are improved in patients with CR at transplant.


Assuntos
Micose Fungoide , Síndrome de Sézary , Humanos , Síndrome de Sézary/terapia , Síndrome de Sézary/mortalidade , Micose Fungoide/terapia , Micose Fungoide/mortalidade , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Transplante de Células-Tronco Hematopoéticas/métodos , Soro Antilinfocitário/uso terapêutico , Soro Antilinfocitário/administração & dosagem , Idoso , Transplante Homólogo/métodos , Taxa de Sobrevida , Estudos Prospectivos , Aloenxertos , Condicionamento Pré-Transplante/métodos , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/etiologia , Resultado do Tratamento
2.
Front Chem ; 11: 1229586, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37476652

RESUMO

Long-lived singlet spin order offers the possibility to extend the spin memory by more than an order of magnitude. This enhancement can be used, among other applications, to assist NMR diffusion experiments in porous media where the extended lifetime of singlet spin order can be used to gain information about structural features of the medium as well as the dynamics of the imbibed phase. Other than offering the possibility to explore longer diffusion times of the order of many minutes that, for example, gives unprecedented access to tortuosity in structures with interconnected pores, singlet order has the important advantage to be immune to the internal field gradients generated by magnetic susceptibility inhomogeneities. These inhomogeneities, however, are responsible for very short T2 decay constants in high magnetic field and this precludes access to the singlet order in the first instance. To overcome this difficulty and take advantage of singlet order in diffusion experiments in porous media, we have here developed a dual-core system with radiofrequency and 3-axis pulsed field gradients facilities in low magnetic field, for preparation and manipulation of singlet order and a probe, in high magnetic field, for polarisation and detection. The system operates in field-cycling and can be used for a variety of NMR experiments including diffusion tensor imaging (both singlet assisted and not). In this paper we present and discuss the new hardware and its calibration, and demonstrate its capabilities through a variety of examples.

3.
J Pharm Biomed Anal ; 219: 114950, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35914505

RESUMO

Rapid analysis of surrendered or seized drug samples provides important intelligence for health (e.g. treatment or harm reduction), and custodial services. Herein, three in-situ techniques, GC-MS, 1H NMR and FT-IR spectroscopy, with searchable libraries, are used to analyse 318 samples qualitatively, using technique specific library-based searches, obtained over the period 24th - 29th August 2019. 259 samples were identified as consisting of a single component, of which cocaine was the most prevalent (n = 158). Median match scores for all three techniques were ≥ 0.84 and showed agreement except for metformin (n = 1), oxandrolone (identified as vitamin K by IR (n = 4)), diazepam (identified as zolpidem by FT-IR (n = 2)) and 2-Br-4,5-DMPEA (n = 1), a structural isomer of 2C-B identified as a polymer of cellulose (cardboard) by FT-IR. 51 samples were found to consist of two or more components, of which 49 were adulterated cocaine samples (45 binary and 4 tertiary samples). GC-MS identified all components present in the 49 adulterated cocaine samples, whereas IR identified only cocaine in 88 % of cases (adulterant only = 12 %). The breakdown for 1H NMR spectroscopy was all components identified (51 %), cocaine only (33 %), adulterant only (10 %), cocaine and one adulterant (tertiary mixtures only, 6 %).


Assuntos
Cocaína , Cocaína/análise , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
4.
J Phys Chem B ; 126(34): 6536-6546, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35976731

RESUMO

The theory of nuclear spin relaxation in a liquid permeating a solid structure of irregular geometry is examined. The effects of restricted diffusion and the demagnetizing field generated by an inhomogeneous distribution of magnetic susceptibility in the system are explored. A framework comprising Brownian Dynamics, average Hamiltonian theory, and Liouville-space spin dynamics is proposed for simulating nuclear spin relaxation in 3D models of random structures obtained from CT scans of actual samples. Simulations results are compared with experimental data. An analytical solution valid within approximation is also reported.

5.
Molecules ; 27(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35056646

RESUMO

In recent years the NMR hyperpolarisation method signal amplification by reversible exchange (SABRE) has been applied to multiple substrates of potential interest for in vivo investigation. Unfortunately, SABRE commonly requires an iridium-containing catalyst that is unsuitable for biomedical applications. This report utilizes inductively coupled plasma-optical emission spectroscopy (ICP-OES) to investigate the potential use of metal scavengers to remove the iridium catalytic species from the solution. The most sensitive iridium emission line at 224.268 nm was used in the analysis. We report the effects of varying functionality, chain length, and scavenger support identity on iridium scavenging efficiency. The impact of varying the quantity of scavenger utilized is reported for the three scavengers with the highest iridium removed from initial investigations: 3-aminopropyl (S1), 3-(imidazole-1-yl)propyl (S4), and 2-(2-pyridyl) (S5) functionalized silica gels. Exposure of an activated SABRE sample (1.6 mg mL-1 of iridium catalyst) to 10 mg of the most promising scavenger (S5) resulted in <1 ppm of iridium being detectable by ICP-OES after 2 min of exposure. We propose that combining the approach described herein with other recently reported approaches, such as catalyst separated-SABRE (CASH-SABRE), would enable the rapid preparation of a biocompatible SABRE hyperpolarized bolus.

6.
Clin Exp Dermatol ; 47(4): 658-666, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34643956

RESUMO

Pruritus is a hallmark of atopic dermatitis (AD), which affects disease severity and patient quality of life. In AD uncontrolled with first-line topical therapies or in moderate to severe AD, systemic therapies are used; however, there is a paucity of head-to-head trials comparing the effectiveness of these therapies. The aim of this study was to compare the effectiveness of systemic therapies in relieving pruritus in moderate to severe AD in adults, using a meta-analysis. The PubMed, EMBASE, Medline and CINAHL databases were searched from inception up to 31 May 2020 for randomized, placebo-controlled trials investigating the effectiveness of systemic therapies on pruritus with moderate to severe AD in patients aged ≥ 16 years. In total, 26 studies (n = 5190 participants) were identified. Compared with placebo, there was a large and statistically significant (P < 0.001 for all) reduction in pruritus [standard mean difference (SMD); 95% CI] with dupilumab every 2 weeks (-0.88; -1.13 to -0.63), dupilumab every 2 weeks plus topical corticosteroids (-0.77; -0.91 to -0.62), dupilumab once weekly (-0.99; -1.29 to -0.68), dupilumab once weekly plus topical corticosteroids (-0.70; -0.81 to -0.59). There was also a large and statistically significant reduction with ciclosporin (-1.30; -2.34 to -0.26; P = 0.01) and a large, although not statistically significant reduction with azathioprine (-0.85; -2.07 to 0.35). There was a small reduction with both mepolizumab (-0.27; -0.89 to 0.35) and interferon-γ (-0.31; -0.75 to 0.12). Of the investigational drugs, nemolizumab 2.0 mg/kg was the most effective (-8.13; -9.31 to -6.94). The majority of systemic therapies were superior to placebo in reducing pruritus. In particular, the dupilumab studies consistently showed large improvements in pruritus, while nemolizumab showed the strongest antipruritic effects. However, future head-to-head trials are required for conclusive evidence.


Assuntos
Dermatite Atópica , Eczema , Adolescente , Adulto , Dermatite Atópica/complicações , Dermatite Atópica/tratamento farmacológico , Humanos , Prurido/tratamento farmacológico , Prurido/etiologia , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Chemphyschem ; 22(11): 1059-1064, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33871116

RESUMO

Mirfentanil, a fentanyl derivative that is a µ-opioid partial agonist, is hyperpolarised via Signal Amplification By Reversible Exchange (SABRE), a para-hydrogen-based technique. [Ir(IMes)(COD)Cl] (IMes=1,3-bis(2,4,6-trimethylphenyl)imidazole-2-ylidene, COD=cyclooctadiene) was employed as the polarisation transfer catalyst. Following polarisation transfer at 6.5 mT, the pyrazine-protons were enhanced by 78-fold (polarisation, P=0.04 %). The complex [Ir(IMes)(H)2 (mirfentanil)2 (MeOH)]+ is proposed to form based on the observation of two hydrides at δ -22.9 (trans to mirfentanil) and -24.7 (trans to methanol). In a mixture of mirfentanil and heroin, the former could be detected using SABRE at concentrations less than 1 % w/w. At the lowest concentration analyzed, the amount of mirfentanil present was 0.18 mg (812 µM) and produced a signal enhancement of -867-fold (P=0.42 %). following polarisation transfer at 6.5 mT.


Assuntos
Fentanila/análogos & derivados , Heroína/química , Fentanila/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
9.
Magn Reson Chem ; 58(12): 1151-1159, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31945193

RESUMO

Piperazine-based drugs, such as N-benzylpiperazine (BZP), became attractive in the 2000s due to possessing effects similar to amphetamines. Herein, BZP, in addition to its pyridyl analogues, 2-, 3-, and 4-pyridylmethylpiperidine (2-PMP, 3-PMP, and 4-PMP respectively) was subjected to the hyperpolarisation technique Signal Amplification By Reversible Exchange (SABRE) in order to demonstrate the use of this technique to detect these piperazine-based drugs. Although BZP was not hyperpolarised via SABRE, 2-PMP, 3-PMP, and 4-PMP were, with the ortho- and meta-pyridyl protons of 4-PMP showing the largest enhancement of 313-fold and 267-fold, respectively, in a 1.4-T detection field, following polarisation transfer at Earth's magnetic field. In addition to the freebase, 4-PMP.3HCl was also appraised by SABRE and was found not to polarise, however, the addition of increasing equivalents of triethylamine (TEA) produced the freebase, with a maximum enhancement observed upon the addition of 3 equivalents of TEA. Further addition of TEA led to a reduction in the observed enhancement. SABRE was also employed to polarise 4-PMP.3HCl (~20% w/w) in a simulated tablet to demonstrate the forensic application of the technique (138-fold enhancement for the ortho-pyridyl protons). The amount of 4-PMP.3HCl present in the simulated tablet was quantified via NMR using D2 O as a solvent and compared well to complimentary gas chromatography-mass spectrometry data. Exchanging D2 O for CD3 OD as the solvent utilised for analysis resulted in a significantly lower amount of 4-PMP.3HCl being determined, thus highlighting safeguarding issues linked to drug abuse in relation to determining the amount of active pharmaceutical ingredient present.


Assuntos
Piperazina/análise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Piperazina/análogos & derivados
11.
ChemistryOpen ; 8(12): 1375-1382, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31844604

RESUMO

Fentanyl, also known as 'jackpot', is a synthetic opiate that is 50-100 times more potent than morphine. Clandestine laboratories produce analogues of fentanyl, known as fentalogues to circumvent legislation regarding its production. Three pyridyl fentalogues were synthesized and then hyperpolarized by signal amplification by reversible exchange (SABRE) to appraise the forensic potential of the technique. A maximum enhancement of -168-fold at 1.4 T was recorded for the ortho pyridyl 1H nuclei. Studies of the activation parameters for the three fentalogues revealed that the ratio of ligand loss trans to hydride and hydride loss in the complex [Ir(IMes)(L)3(H)2]+ (IMes=1,3-bis(2,4,6-trimethylphenyl)imidazole-2-ylidene) ranged from 0.52 to 1.83. The fentalogue possessing the ratio closest to unity produced the largest enhancement subsequent to performing SABRE at earth's magnetic field. It was possible to hyperpolarize a pyridyl fentalogue selectively from a matrix that consisted largely of heroin (97 : 3 heroin:fentalogue) to validate the use of SABRE as a forensic tool.

12.
ACS Omega ; 4(4): 7103-7112, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31179411

RESUMO

An automated approach to the collection of 1H NMR (nuclear magnetic resonance) spectra using a benchtop NMR spectrometer and the subsequent analysis, processing, and elucidation of components present in seized drug samples are reported. An algorithm is developed to compare spectral data to a reference library of over 300 1H NMR spectra, ranking matches by a correlation-based score. A threshold for identification was set at 0.838, below which identification of the component present was deemed unreliable. Using this system, 432 samples were surveyed and validated against contemporaneously acquired GC-MS (gas chromatography-mass spectrometry) data. Following removal of samples which possessed no peaks in the GC-MS trace or in both the 1H NMR spectrum and GC-MS trace, the remaining 416 samples matched in 93% of cases. Thirteen of these samples were binary mixtures. A partial match (one component not identified) was obtained for 6% of samples surveyed whilst only 1% of samples did not match at all.

13.
ChemistryOpen ; 7(1): 97-105, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29318102

RESUMO

Fluorinated ligands have a variety of uses in chemistry and industry, but it is their medical applications as 18F-labelled positron emission tomography (PET) tracers where they are most visible. In this work, we illustrate the potential of using 19F-containing ligands as future magnetic resonance imaging (MRI) contrast agents and as probes in magnetic resonance spectroscopy studies by significantly increasing their magnetic resonance detectability through the signal amplification by reversible exchange (SABRE) hyperpolarization method. We achieve 19F SABRE polarization in a wide range of molecules, including those essential to medication, and analyze how their steric bulk, the substrate loading, polarization transfer field, pH, and rate of ligand exchange impact the efficiency of SABRE. We conclude by presenting 19F MRI results in phantoms, which demonstrate that many of these agents show great promise as future 19F MRI contrast agents for diagnostic investigations.

14.
Clin Exp Dermatol ; 38(8): 851-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23782061

RESUMO

INTRODUCTION: Sun exposure is a major risk factor for the development of skin cancer. This is particularly relevant in immunosuppressed liver-transplant recipients (LTRs). Preventative strategies may help minimize the skin-cancer risk in this patient group. METHODS: We assessed 670 patients in our post-transplant clinic, using questionnaires. Patient data were collected, and we assessed whether patients had received education (such as formal talks or information from transplant coordinators or from hepatologists) on skin, sun exposure and skin cancer. In a subset of 280 of the LTRs who responded, we recorded their recall of sun-protection advice and assessed the level of patient adherence to such advice. RESULTS: The response rate was 57.5% (349/607), with a mean responder age of 51.1 years (range 19-84) and an average post-transplant time of 7.1 years (range 0-27). In the recall assessment, 37.2% reported that they were given advice about their skin, while 18.1% were seen by a dermatologist, and education on sun exposure and the risks of skin cancer was given to 65.6% and 47.9%, respectively. Over three-quarters (78%; 185/280) of the patients used mechanical sun protection (i.e. hats/clothing), while 66% reported using sunscreen; 31.8% of these used a sunscreen of the recommended sun protection factor (SPF) of > 30. Twelve patients had developed squamous cell carcinoma after a mean of 10.9 years (1-23) post-transplant; half of these had used either no sunscreen or one with an SPF of < 15. CONCLUSIONS: Despite the fact that LTRs are given information on sun-exposure and SC before and after transplantation, recall of such advice and use of sun-protection methods was only moderate, indicating that regular reinforcement of SC education is needed.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Transplante de Fígado/efeitos adversos , Educação de Pacientes como Assunto/normas , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Neoplasias Cutâneas/etiologia , Protetores Solares , Inquéritos e Questionários , Adulto Jovem
15.
J Hazard Mater ; 182(1-3): 631-9, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20638784

RESUMO

This work investigated the toxicity of two isomeric alkylphthalates, i.e., di-n-octyl phthalate (DOP) and di-2-ethylhexyl phthalate (DEHP) to two model bacteria, Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis), which have been previously used to study the toxicity of environmental pollutants. Microcalorimetry was used as the key analytical tool alongside scanning electron microscopy (SEM) and traditional microbiology techniques. The thermokinetic parameters from microcalorimetry showed that the phthalates had a biphasic effect on the metabolic activities of the bacteria; serving as energy sources for the bacteria thereby stimulating their growth at low dosages (< or = 150 microg/mL), but displaying inhibitory effects at higher dosages (> or = 300 microg/mL), indicated by a sharp decrease in growth rate constants at 450 microg/mL. The SEM revealed that the bacterial cells were morphological deformed, with shrunk cells and elongated strands at 600 microg/mL of both phthalates. The elongated strands inferred that the phthalates inhibited the reproductive processes of the bacteria by possibly impeding some stages of cell division. The half inhibitory concentrations of the phthalates showed that DEHP was more toxic than DOP. Additionally, E. coli, a facultative anaerobe, was more susceptible to the toxic effects of phthalates than B. subtilis, an obligate aerobe capable of forming endospores crucial for tolerating extreme environmental conditions.


Assuntos
Bacillus subtilis/metabolismo , Escherichia coli/metabolismo , Ácidos Ftálicos/toxicidade , Calorimetria/métodos , Isomerismo , Cinética , Microscopia Eletrônica de Varredura , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo
16.
Phys Rev Lett ; 95(21): 215004, 2005 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-16384150

RESUMO

The first hohlraum experiments on the National Ignition Facility (NIF) using the initial four laser beams tested radiation temperature limits imposed by plasma filling. For a variety of hohlraum sizes and pulse lengths, the measured x-ray flux shows signatures of filling that coincide with hard x-ray emission from plasma streaming out of the hohlraum. These observations agree with hydrodynamic simulations and with an analytical model that includes hydrodynamic and coronal radiative losses. The modeling predicts radiation temperature limits with full NIF (1.8 MJ), greater, and of longer duration than required for ignition hohlraums.

17.
Phys Rev Lett ; 94(5): 055006, 2005 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-15783658

RESUMO

A series of experiments conducted on the HELEN laser system [M. J. Norman, Appl. Opt.4120023497], into thermal x-ray generation from hohlraum targets using 527 nm (2omega) wavelength laser light, has shown that it is possible to exceed radiation temperatures previously thought limited by high levels of superthermal or hot electron production or stimulated backscatter. This Letter questions whether the assumptions traditionally applied to hohlraum design with respect to hot plasma filling and the use of 2omega light are too conservative.

18.
Acta Crystallogr D Biol Crystallogr ; 60(Pt 4): 621-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15039549

RESUMO

Phase-contrast X-ray diffraction imaging and high-angular-resolution diffraction combined with phase-contrast radiographic imaging were employed to characterize defects and perfection of a uniformly grown tetragonal lysozyme crystal in the symmetric Laue case. The full-width at half-maximum (FWHM) of a 4 4 0 rocking curve measured from the original crystal was approximately 16.7 arcsec and imperfections including line defects, inclusions and other microdefects were observed in the diffraction images of the crystal. The observed line defects carry distinct dislocation features running approximately along the <1 1 0> growth front and have been found to originate mostly in a central growth area and occasionally in outer growth regions. Inclusions of impurities or formations of foreign particles in the central growth region are resolved in the images with high sensitivity to defects. Slow dehydration led to the broadening of a fairly symmetric 4 4 0 rocking curve by a factor of approximately 2.6, which was primarily attributed to the dehydration-induced microscopic effects that are clearly shown in X-ray diffraction images. The details of the observed defects and the significant change in the revealed microstructures with drying provide insight into the nature of imperfections, nucleation and growth, and the properties of protein crystals.


Assuntos
Muramidase/química , Animais , Galinhas , Cristalização , Cristalografia por Raios X , Estrutura Molecular , Transição de Fase , Água/química
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(6 Pt 1): 061914, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12513324

RESUMO

Surface x-ray diffraction measurements were performed on (111) growth faces of crystals of the cellular iron-storage protein, horse spleen ferritin. Crystal truncation rods (CTR) were measured. A fit of the measured profile of the CTR revealed a surface roughness of 48+/-4.5 A and a top layer spacing contraction of 3.9+/-1.5%. In addition to the peak from the CTR, the rocking curves of the crystals displayed unexpected extra peaks. Multiple scattering is demonstrated to account for them. Future applications of the method could allow the exploration of hydration effects on the growth of protein crystals.

20.
Phys Rev Lett ; 87(14): 148101, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11580675

RESUMO

Conventional x-ray diffraction topography is currently used to map defects in the bulk of protein crystals, but the lack of sufficient contrast is frequently a limiting factor. We experimentally demonstrate that this barrier can be circumvented using a method that combines phase sensitive and diffraction imaging principles. Details of defects revealed in tetragonal lysozyme and cubic ferritin crystals are presented and discussed. The approach enabling the detection of the phase changes of diffracted x rays should prove to be useful in the study of defect structures in a broad range of biological macromolecular crystals.


Assuntos
Ferritinas/química , Muramidase/química , Animais , Galinhas , Cristalização , Proteínas do Ovo/química , Feminino , Difração de Raios X
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