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1.
J Diet Suppl ; : 1-16, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38269549

RESUMO

The DSHEA is 30 years old and its place in providing legitimate protections for public health through relevant agency oversight has created a patchwork of legal and scientific requirements. In contrast, the European Union has rules on supplements and permitted ingredients. Given the context of a global supply chain for food ingredients any conflict between the legality of ingredients between the U.S/EU can inhibit the economic viability of international trade. The purpose of this review is to contrast these different systems of legislative oversight. The analysis of both markets demonstrates a fragmentation in what are considered legal food ingredients between country wide harmonization and state rules and related interpretation. There are many commonalities in this regard between the U.S/EU, from borderline medicinal classifications to their resultant preclusion from food use. However, the codified legal system existing within the EU and excessive guidance can be viewed as time consuming and inflexible, especially for placing new ingredients on the market. The US in contrast is in a holding pattern for legislative interpretation regarding NDIs, GRAS and possible drug preclusion laws. As we hit the anniversary of the DSHEA recent commentary from U.S./EU central authorities point to increased international co-operation in ingredient safety assessments but whether this results in friction-free access between markets is to be determined.

2.
Clin Transl Oncol ; 21(12): 1763-1770, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31598904

RESUMO

INTRODUCTION: Cancer and blood disorders in children are rare. The progressive improvement in survival over the last decades largely relies on the development of international academic clinical trials that gather the sufficient number of patients globally to elaborate solid conclusions and drive changes in clinical practice. The participation of Spain into large international academic trials has traditionally lagged behind of other European countries, mainly due to the burden of administrative tasks to open new studies, lack of financial support and limited research infrastructure in our hospitals. METHODS: The objective of ECLIM-SEHOP platform (Ensayos Clínicos Internacionales Multicéntricos-SEHOP) is to overcome these difficulties and position Spain among the European countries leading the advances in cancer and blood disorders, facilitate the access of our patients to novel diagnostic and therapeutic approaches and, most importantly, continue to improve survival and reducing long-term sequelae. ECLIM-SEHOP provides to the Spanish clinical investigators with the necessary infrastructural support to open and implement academic clinical trials and registries. RESULTS: In less than 3 years from its inception, the platform has provided support to 20 clinical trials and 8 observational studies, including 8 trials and 4 observational studies where the platform performs all trial-related tasks (integral support: trial setup, monitoring, etc.) with more than 150 patients recruited since 2017 to these studies. In this manuscript, we provide baseline metrics for academic clinical trial performance that permit future comparisons. CONCLUSIONS: ECLIM-SEHOP facilitates Spanish children and adolescents diagnosed with cancer and blood disorders to access state-of-the-art diagnostic and therapeutic strategies.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Cooperação Internacional , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Estudos Observacionais como Assunto/estatística & dados numéricos , Objetivos Organizacionais , Sociedades Médicas/organização & administração , Adolescente , Sobreviventes de Câncer , Criança , Neoplasias Hematológicas/terapia , Hematologia/organização & administração , Humanos , Oncologia/organização & administração , Neoplasias/terapia , Pediatria/organização & administração , Espanha
3.
J Opt Soc Am A Opt Image Sci Vis ; 27(11): A9-18, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21045895

RESUMO

Extremely Large Telescopes (ELTs) are very challenging with respect to their adaptive optics (AO) requirements. Their diameters and the specifications required by the astronomical science for which they are being designed imply a huge increment in the number of degrees of freedom in the deformable mirrors. Faster algorithms are needed to implement the real-time reconstruction and control in AO at the required speed. We present the results of a study of the AO correction performance of three different algorithms applied to the case of a 42-m ELT: one considered as a reference, the matrix-vector multiply (MVM) algorithm; and two considered fast, the fractal iterative method (FrIM) and the Fourier transform reconstructor (FTR). The MVM and the FrIM both provide a maximum a posteriori estimation, while the FTR provides a least-squares one. The algorithms are tested on the European Southern Observatory (ESO) end-to-end simulator, OCTOPUS. The performance is compared using a natural guide star single-conjugate adaptive optics configuration. The results demonstrate that the methods have similar performance in a large variety of simulated conditions. However, with respect to system misregistrations, the fast algorithms demonstrate an interesting robustness.

4.
Amino Acids ; 30(3): 279-89, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16554972

RESUMO

Beta-alanine in blood-plasma when administered as A) histidine dipeptides (equivalent to 40 mg . kg(-1) bwt of beta-alanine) in chicken broth, or B) 10, C) 20 and D) 40 mg . kg(-1) bwt beta-alanine (CarnoSyn, NAI, USA), peaked at 428 +/- SE 66, 47 +/- 13, 374 +/- 68 and 833 +/- 43 microM. Concentrations regained baseline at 2 h. Carnosine was not detected in plasma with A) although traces of this and anserine were found in urine. Loss of beta-alanine in urine with B) to D) was <5%. Plasma taurine was increased by beta-alanine ingestion but this did not result in any increased loss via urine. Pharmacodynamics were further investigated with 3 x B) per day given for 15 d. Dietary supplementation with I) 3.2 and II) 6.4 g . d(-1) beta-alanine (as multiple doses of 400 or 800 mg) or III) L-carnosine (isomolar to II) for 4 w resulted in significant increases in muscle carnosine estimated at 42.1, 64.2 and 65.8%.


Assuntos
Carnosina/metabolismo , Suplementos Nutricionais , Músculo Quadríceps/metabolismo , beta-Alanina/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Dipeptídeos/administração & dosagem , Dipeptídeos/farmacocinética , Humanos , Masculino , Taurina/sangue , Taurina/urina , beta-Alanina/administração & dosagem
5.
Aten Primaria ; 33(2): 78-85, 2004 Feb 15.
Artigo em Espanhol | MEDLINE | ID: mdl-14967124

RESUMO

OBJECTIVES: To find the social and clinical characteristics of patients over-using (OUP) our centre. To find how much these patients use the health services. DESIGN: Observational, descriptive study. SETTING: Urban primary care centre (36 408 inhabitants). PARTICIPANTS: Patients over 15 seen at the centre during the year 2000, who exceeded in their number of attendances the mean plus two standard deviations for their age group. MAIN MEASUREMENTS: The records of OUPS were reviewed to analyse their social and demographic characteristics, kinds of attendance, reasons for consultation, further tests, medication, referrals, and time off work this year. RESULTS: The sample was of 954 OUPs, 50.9% of whom were male with an average age of 50.54 (SD, 19.68). 86.3% had some risk factor recorded (34% hypertension, 32.4% mental health, 27.7% obesity, 25.7% tobacco dependency, 17.7% diabetes mellitus). They generated a mean of 9.6 visits to the doctor per year, with 95% CI (8.09-11.19), with the most common reason for attendance the monitoring of acute pathology (19.29%), followed by monitoring of chronic pathology (14.32%). There was an average of 1 analysis per OUP per year, and 0.68 image tests per OUP per year (48.38% were simple x-rays). 46.8% of the medication prescribed were analgesics. Average time off work was 0.5 periods off per OUP per year, with a mean period of 49.4 days off (SD, 113.69). They engendered an average of 4.15 nursing visits per OUP per year, 95% CI (2.60-5.70), with monitoring of chronic pathology the most common reason for consultation. 30.3% of OUP had a visit to hospital casualty recorded, with osteo-muscular pathology the most common reason for consultation (34.29%). Mean referrals were 0.88 OUP per year, with traumatology being the department to which most referrals were made (13.92%). CONCLUSIONS: OUP are middle-aged, have associated chronic pathology and use programmed appointments a lot. The additional tests conducted matched the centre's procedures for monitoring chronic pathologies. The most common reason for attendance at casualty was traumatology, as was the specialist clinic to which most referrals were made.


Assuntos
Serviços de Saúde/estatística & dados numéricos , Visita a Consultório Médico/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Adolescente , Adulto , Idoso , Estudos Transversais , Medicina de Família e Comunidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos
6.
J Opt Soc Am A Opt Image Sci Vis ; 17(12): 2236-42, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11140483

RESUMO

We report the photometric observation of a polychromatic laser guide star (PLGS) using the AVLIS laser at the Lawrence Livermore National Laboratory (LLNL). The process aims at providing a measurement of the tilt of the incoming wave front at a telescope induced by atmospheric turbulence. It relies on the two-photon coherent excitation of the 4D5/2 energy level of sodium atoms in the mesosphere. We used two laser beams at 589 and 569 nm, with a maximum total average output power of approximately 350 W. For the purpose of photometric calibration, a natural star was observed simultaneously through the same instrument as the PLGS at the focus of the LLNL 50-cm telescope. Photometric measurements of the 330-nm return flux confirm our previous theoretical studies that the PLGS process should allow us at a later stage to correct for the tilt at wavelengths as short as approximately 1 microm at good astronomical sites. They show also that, at saturation of two-photon coherent absorption in the mesosphere, the backscattered flux increases by a factor of approximately 2 when the pulse repetition rate decreases by a factor of 3 at constant average power. This unexpected behavior is briefly discussed.

7.
Appl Opt ; 35(10): 1751-5, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21085298

RESUMO

Up to now only a few numerical or experimental simulations of atmospheric turbulent layers have been performed in the laboratory. These are devoted mainly to show the validity of Kolmogorov behavior but are not suitable to implement in an optical bench to test light propagation. Here we present a small size experimental simulation of an optical turbulent layer. With optical and in situ measurements, we managed to determine its characteristics: the mean variance of the refractive-index fluctuations integrated over the thickness of the turbulent flow and longitudinal and transverse structure functions of angles of arrival. From these measurements we found that the power spectrum of the refractive index is well fitted by a Von Karman function with an outer scale of 91 mm and an inner scale of 4.7 mm. Moreover, the temporal stationarity of these parameters indicates the reproducibility of this simulated turbulent flow.

8.
Biopolymers ; 34(5): 679-89, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8003625

RESUMO

The receptor for the alpha-factor mating pheromone of the yeast Saccharomyces cerevisiae consists of 431 amino acid residues and is a member of a family of membrane proteins predicted to have seven transmembrane helices. Fragments of the receptor corresponding to two of the transmembrane helices [residues 246-269 (M6) and 273-302 (M7)], two of the interhelical loops [residues 107-125 (E2) and 191-206 (E3)], and to a portion of the carboxyl terminus [residues 350-372 (CT)] were synthesized using solid-phase methodologies and purified to near homogeneity. CD was used to characterize the secondary structure of these peptides in trifluoroethanol (TFE), in TFE/water mixtures, in sodium dodecyl sulfate (SDS), and in the presence of dimyristoyl phosphatidylcholine (DMPC) liposomes. In TFE, M6 and M7 exhibited CD spectra consistent with highly helical peptides, whereas CT was partially helical. In contrast, E2 and E3 were either disordered or aggregated in this solvent. M6 did not partition well into DMPC vesicles whereas M7 remained helical. Both M6 and M7 assumed helical conformations in 25 mM SDS. The loop peptides and the carboxyl terminus peptide were either in a beta-structure or disordered in the presence of lipid. These findings represent the first biophysical evidence for conformations assumed by specific segments of the STE2 receptor protein.


Assuntos
Receptores de Peptídeos/química , Fatores de Transcrição , Sequência de Aminoácidos , Fenômenos Biofísicos , Biofísica , Dicroísmo Circular , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Estrutura Secundária de Proteína , Receptores de Fator de Acasalamento , Saccharomyces cerevisiae
9.
Biopolymers ; 33(6): 915-26, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7686410

RESUMO

A highly potent and selective agonist to the tachykinin NK-3 receptor, [pGlu6,N-MePhe8,Aib9] substance P (6-11) (I), was synthesized via the solid phase method. The ED50 of I was 4 nM in the guinea pig ileum in the absence of atropine (NK-1+NK-3 receptors) and this agonist was 5000-fold less potent in the presence of atropine (NK-1 receptor). The analogue was virtually inactive in the rat vas deferens (NK-2 receptor). A detailed analysis of the solution conformation of this analogue in DMSO-d6 and in a DMSO-d6/H2O cryomixture was carried out by a combination of 1H-nmr 2D techniques (DQF-COSY, TOCSY, NOESY and ROESY) and model building based on empirical energy calculations. Peptide I exists as a mixture of isomers containing cis and trans Phe-N-MePhe peptide bonds. The main isomer, containing a cis Phe-N-MePhe peptide bond, shows a preferred folded conformation characterized by a type VI beta-turn with Phe and N-MePhe in the i + 1 and i + 2 positions. The turn is followed by a helical segment extending to the C-terminal. This conformation is compared to previously reported conformations of other selective tachykinin agonists and may be a promising lead for the design of novel NK-3 agonists with additional conformational constraints.


Assuntos
Fragmentos de Peptídeos/química , Receptores de Neurotransmissores/fisiologia , Substância P/análogos & derivados , Sequência de Aminoácidos , Animais , Cobaias , Técnicas In Vitro , Masculino , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/farmacologia , Conformação Proteica , Ácido Pirrolidonocarboxílico/análogos & derivados , Ratos , Receptores de Taquicininas , Substância P/síntese química , Substância P/química , Substância P/farmacologia
10.
Appl Opt ; 31(32): 6902-8, 1992 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-20733929

RESUMO

An analysis of the problem of wave-front reconstruction from Shack-Hartmann measurements is presented. The wave-front aberration is assumed to result from passage of the wave front through Kolmogorov turbulence. Limitations of using Zernike polynomials as an orthogonal basis for wave-front reconstruction are highlighted, and the advantage of using the Karhunen-Loeve functions for computing the higher-order modes of the wave front is shown.

11.
J Med Chem ; 33(2): 514-20, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2299622

RESUMO

The shape of the active site of the receptor for sweet molecules was previously defined on the basis of a combination of both rigid (saccharins) and flexible (aspartame) molds. In this paper, the sweetness receptor is refined with use of the shapes of 3-anilino-2-styryl-3H-naphtho[1,2-d]imidazolesulfonate (sweet) and of 3-anilino-2-phenyl-3H-naphtho[1,2-d]imidazolesulfonate (tasteless), two large and almost completely rigid tastants. The minimum-energy conformations of the flexible portions of these tastants have been determined by using a detailed conformational analysis based on ab initio calculations. The refined receptor site is still consistent with all previously examined sweet molecules. In order to unequivocally assign the prochiral beta-CH2 protons of the Phe moiety of aspartame, (2S,3S)-[2H]-alpha-L-Asp-L-PheOMe was synthesized and examined by 500-MHz 1H NMR spectroscopy. The results indicate that the minimum-energy conformation for aspartame in water, DMSO-d6, and CDCl3 (as a crown ether complex) is different from that originally proposed (FIIDII instead of FIDII, according to a notation referred to the side chains). Although this conformation is not directly consistent with the shape of the sweet receptor, the interconversion of FIIDII to FIDII was found to require only 1 kcal/mol. Furthermore, a 120-ps molecular dynamics simulation in vacuo confirms the high flexibility of aspartame and the accessibility of the FIDII conformer whose topology is fully consistent with our model.


Assuntos
Aspartame , Dipeptídeos , Imidazóis , Naftalenos , Ácidos Sulfônicos , Edulcorantes , Espectroscopia de Ressonância Magnética , Conformação Molecular , Relação Estrutura-Atividade , Paladar/fisiologia , Termodinâmica
12.
Biopolymers ; 29(1): 237-45, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2158359

RESUMO

The binding of the tridecapeptide yeast mating pheromone, alpha-factor, to its receptor represents an excellent model for the investigation of peptide hormone-receptor interactions. In this paper we present a number of strategies to probe the binding site of the alpha-factor receptor, and discuss the synthesis of probes containing radioactive and affinity tags. Preferential acylation of the alpha- or epsilon-amine in [Nle12]-alpha-factor was accomplished using 3-[3,5-diiodo-4-hydroxyphenyl] propanoic acid hydroxysuccinimide ester (diiodo Bolton-Hunter reagent). At pH 8.0 in a N-N-dimethylformamide/water mixture the ratio of epsilon- to alpha-acylation was 2.15 to 1, whereas at pH 6.5 in a 1,2-dimethoxyethane/water mixture alpha-acylation was favored by more than 3 to 1. The product distribution was found to depend on pH, organic cosolvent, and the ratio of organic solvent and aqueous buffer. Product distributions were followed using analytical high performance liquid chromatography and the products were characterized enzymatically and by mass spectrometry. Citraconic anhydride preferentially alpha-acylated [Nle12]-alpha-factor and served as a temporary masking group during the synthesis of epsilon-Bolton-Hunter acylated pheromone. Biotin or diiodo Bolton-Hunter reagents were also directly incorporated into [Nle12]-alpha-factor or Lys[Nle12]-alpha-factor during peptide synthesis. The peptides were assembled on a chloromethyl polystyrene resin or on a (phenylacetamido)methyl resin, and cleaved using anhydrous hydrogen fluoride (HF). Probes were inserted on amino groups either prior (biotin) or subsequent (Bolton-Hunter reagent) to HF cleavage. The biological activity of the synthetic peptides was characterized using growth arrest assays.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Sondas Moleculares , Peptídeos/metabolismo , Feromônios/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Peptídeos , Fatores de Transcrição , Sequência de Aminoácidos , Sítios de Ligação , Concentração de Íons de Hidrogênio , Fator de Acasalamento , Sondas Moleculares/síntese química , Dados de Sequência Molecular , Receptores de Fator de Acasalamento
13.
Biochemistry ; 26(24): 7767-74, 1987 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3322407

RESUMO

The synthesis and biological activity are reported for extended analogues of the secreted tridecapeptide alpha-factor (Trp-His-Trp-Leu-Gln-Leu-Lys-Pro-Gly-Gln-Pro-Met-Tyr) from Saccharomyces cerevisiae. Peptides with Ala, Glu-Ala, Ala-Glu-Ala, or Glu-Ala-Glu-Ala attached to the amino terminus of alpha-factor were synthesized by the solid-phase method on a (phenylacetamido)methyl (PAM) resin, using a combination of dicyclohexylcarbodiimide- and 1-hydroxybenzotriazole-accelerated active ester coupling procedures. Free peptides were obtained by hydrogen fluoride (HF) cleavage in the presence of appropriate scavengers. Normal high HF cleavage and "low-high" HF cleavage were equally effective in liberating the desired product from the PAM resin. Yields of pure peptide ranged from 9% to 17%. All of the extended alpha-factors, which represent sequences of pro-alpha-factor coded for in the MF alpha 1 structural gene, caused morphological aberrations (shmoo assay) in strain X2180-1A (MATa) the same as those caused by the tridecapeptide. The 14-peptide was equally active compared to the native alpha-factor whereas the 17-peptide was 5-10-fold less active. The analogues also arrested to various degrees (halo assay) the growth of S. cerevisiae RC629 (MATa sst1) and S. cerevisiae RC631 (MATa sst2), two supersensitive mutants, and were converted to pheromones of equal activity by treatment with V8 protease. A temperature-sensitive receptor mutant responded to all the peptides at the permissive but not the restrictive temperature. An alpha-factor antagonist, des-Trp1,Ala3-alpha-factor, inhibited activity of all extended peptides.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Peptídeos/síntese química , Feromônios/síntese química , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Genótipo , Indicadores e Reagentes , Fator de Acasalamento , Peptídeos/farmacologia , Fenótipo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/efeitos dos fármacos , Relação Estrutura-Atividade
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