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1.
Rheumatology (Oxford) ; 63(4): 999-1006, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-37354498

RESUMEN

OBJECTIVE: Data on ANCA-associated vasculitis (AAV) induced by anti-thyroid drugs (ATD) are scarce. We aimed to describe the characteristics and outcome of these patients in comparison to primary AAV. METHODS: We performed a retrospective multicentre study including patients with ATD-induced AAV. We focused on ATD-induced microscopic polyangiitis (MPA) and compared them with primary MPA by matching each case with four controls by gender and year of diagnosis. RESULTS: Forty-five patients with ATD-induced AAV of whom 24 MPA were included. ANCA were positive in 44 patients (98%), including myeloperoxidase (MPO)-ANCA in 21 (47%), proteinase 3 (PR3)-ANCA in six (13%), and double positive MPO- and PR3-ANCA in 15 (33%). Main clinical manifestations were skin involvement (64%), arthralgia (51%) and glomerulonephritis (20%). ATD was discontinued in 98% of cases, allowing vasculitis remission in seven (16%). All the remaining patients achieved remission after glucocorticoids, in combination with rituximab in 11 (30%) or cyclophosphamide in four (11%). ATD were reintroduced in seven cases (16%) without any subsequent relapse. Compared with 96 matched primary MPA, ATD-induced MPA were younger at diagnosis (48 vs 65 years, P < 0.001), had more frequent cutaneous involvement (54 vs 25%, P = 0.007), but less frequent kidney (38 vs 73%, P = 0.02), and a lower risk of relapse (adjusted HR 0.07; 95% CI 0.01, 0.65, P = 0.019). CONCLUSION: ATD-induced AAV were mainly MPA with MPO-ANCA, but double MPO- and PR3-ANCA positivity was frequent. The most common manifestations were skin and musculoskeletal manifestations. ATD-induced MPA were less severe and showed a lower risk of relapse than primary MPA.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Granulomatosis con Poliangitis , Poliangitis Microscópica , Humanos , Granulomatosis con Poliangitis/diagnóstico , Estudios Retrospectivos , Anticuerpos Anticitoplasma de Neutrófilos , Estudios de Casos y Controles , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/diagnóstico , Mieloblastina , Recurrencia , Peroxidasa
2.
Eur J Endocrinol ; 188(3)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36806620

RESUMEN

OBJECTIVE: The adipogenic PPARG-encoded PPARγ nuclear receptor also displays essential placental functions. We evaluated the metabolic, reproductive, and perinatal features of patients with PPARG-related lipodystrophy. METHODS: Current and retrospective data were collected in patients referred to a National Rare Diseases Reference Centre. RESULTS: 26 patients from 15 unrelated families were studied (18 women, median age 43 years). They carried monoallelic PPARG variants except a homozygous patient with congenital generalized lipodystrophy. Among heterozygous patients aged 16 or more (n = 24), 92% had diabetes, 96% partial lipodystrophy (median age at diagnosis 24 and 37 years), 78% hypertriglyceridaemia, 71% liver steatosis, and 58% hypertension. The mean BMI was 26 ± 5.0 kg/m2. Women (n = 16) were frequently affected by acute pancreatitis (n = 6) and/or polycystic ovary syndrome (n = 12). Eleven women obtained one or several pregnancies, all complicated by diabetes (n = 8), hypertension (n = 4), and/or hypertriglyceridaemia (n = 10). We analysed perinatal data of patients according to the presence (n = 8) or absence (n = 9) of a maternal dysmetabolic environment. The median gestational age at birth was low in both groups (37 and 36 weeks of amenorrhea, respectively). As expected, the birth weight was higher in patients exposed to a foetal dysmetabolic environment of maternal origin. In contrast, 85.7% of non-exposed patients, in whom the variant is, or is very likely to be, paternally-inherited, were small for gestational age. CONCLUSIONS: Lipodystrophy-related PPARG variants induce early metabolic complications. Our results suggest that placental expression of PPARG pathogenic variants carried by affected foetuses could impair prenatal growth and parturition. This justifies careful pregnancy monitoring in affected families.


Asunto(s)
Hipertensión , Hipertrigliceridemia , Lipodistrofia , Pancreatitis , Recién Nacido , Humanos , Femenino , Embarazo , Adulto , PPAR gamma/genética , Estudios Retrospectivos , Enfermedad Aguda , Placenta , Parto
3.
EBioMedicine ; 84: 104246, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36099812

RESUMEN

BACKGROUND: Primary Ovarian Insufficiency (POI), a public health problem, affects 1-3.7% of women under 40 yielding infertility and a shorter lifespan. Most causes are unknown. Recently, genetic causes were identified, mostly in single families. We studied an unprecedented large cohort of POI to unravel its molecular pathophysiology. METHODS: 375 patients with 70 families were studied using targeted (88 genes) or whole exome sequencing with pathogenic/likely-pathogenic variant selection. Mitomycin-induced chromosome breakages were studied in patients' lymphocytes if necessary. FINDINGS: A high-yield of 29.3% supports a clinical genetic diagnosis of POI. In addition, we found strong evidence of pathogenicity for nine genes not previously related to a Mendelian phenotype or POI: ELAVL2, NLRP11, CENPE, SPATA33, CCDC150, CCDC185, including DNA repair genes: C17orf53(HROB), HELQ, SWI5 yielding high chromosomal fragility. We confirmed the causal role of BRCA2, FANCM, BNC1, ERCC6, MSH4, BMPR1A, BMPR1B, BMPR2, ESR2, CAV1, SPIDR, RCBTB1 and ATG7 previously reported in isolated patients/families. In 8.5% of cases, POI is the only symptom of a multi-organ genetic disease. New pathways were identified: NF-kB, post-translational regulation, and mitophagy (mitochondrial autophagy), providing future therapeutic targets. Three new genes have been shown to affect the age of natural menopause supporting a genetic link. INTERPRETATION: We have developed high-performance genetic diagnostic of POI, dissecting the molecular pathogenesis of POI and enabling personalized medicine to i) prevent/cure comorbidities for tumour/cancer susceptibility genes that could affect life-expectancy (37.4% of cases), or for genetically-revealed syndromic POI (8.5% of cases), ii) predict residual ovarian reserve (60.5% of cases). Genetic diagnosis could help to identify patients who may benefit from the promising in vitro activation-IVA technique in the near future, greatly improving its success in treating infertility. FUNDING: Université Paris Saclay, Agence Nationale de Biomédecine.


Asunto(s)
Infertilidad , Insuficiencia Ovárica Primaria , Femenino , Humanos , Infertilidad/complicaciones , Mitomicinas , FN-kappa B , Medicina de Precisión , Insuficiencia Ovárica Primaria/etiología
5.
J Clin Endocrinol Metab ; 106(12): 3505-3514, 2021 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-34333603

RESUMEN

CONTEXT: Cardiovascular disease is the leading cause of death in patients with Cushing syndrome. Cortisol excess and adverse metabolic profile could increase cardiac fat, which can subsequently impair cardiac structure and function. OBJECTIVE: We aimed to evaluate cardiac fat mass and distribution in patients with Cushing syndrome. METHODS: In this prospective, cross-sectional study, 23 patients with Cushing syndrome and 27 control individuals of comparable age, sex, and body mass index were investigated by cardiac magnetic resonance imaging and proton spectroscopy. Patients were explored before and after biochemical disease remission. Myocardial fat measured by the Dixon method was the main outcome measure. The intramyocardial triglyceride/water ratio measured by spectroscopy and epicardial and pericardial fat volumes were secondary outcome measures. RESULTS: No difference was found between patients and controls in intramyocardial lipid content. Epicardial fat mass was increased in patients compared to controls (30.8 g/m2 [20.4-34.8] vs 17.2 g/m2 [13.1-23.5], P < .001). Similarly, pericardial fat mass was increased in patients compared to controls (28.3 g/m2 [17.9-38.0] vs 11.4 g/m2 [7.5-19.4], P = .003). Sex, glycated hemoglobin A1c, and the presence of hypercortisolism were independent determinants of epicardial fat. Pericardial fat was associated with sex, impaired glucose homeostasis and left ventricular wall thickness. Disease remission decreased epicardial fat mass without affecting pericardial fat. CONCLUSION: Intramyocardial fat stores are not increased in patients with Cushing syndrome, despite highly prevalent metabolic syndrome, suggesting increased cortisol-mediated lipid consumption. Cushing syndrome is associated with marked accumulation of epicardial and pericardial fat. Epicardial adiposity may exert paracrine proinflammatory effects promoting cardiomyopathy.


Asunto(s)
Adiposidad , Índice de Masa Corporal , Cardiomiopatías/patología , Síndrome de Cushing/fisiopatología , Grasa Intraabdominal/patología , Miocardio/patología , Pericardio/patología , Adulto , Biomarcadores/análisis , Glucemia/análisis , Cardiomiopatías/epidemiología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos
6.
Eur J Endocrinol ; 172(2): 141-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25411236

RESUMEN

CONTEXT: Mitotane is an adrenolytic and anticortisolic drug used in adrenocortical carcinoma (ACC), Cushing's disease (CD), and ectopic ACTH syndrome. Its effects on the ovaries are unknown. OBJECTIVE: To evaluate the ovarian and gonadotrope effects of mitotane therapy in premenopausal women. PATIENTS: We studied 21 premenopausal women (ACC: n=13; CD: n=8; median age 33 years, range 18-45 years) receiving mitotane at a median initial dose of 3 g/day (range 1.5-6 g/day). METHODS: Gynecological history was collected and ovarian ultrasound was performed. Four women also underwent ovarian CT or magnetic resonance imaging. Serum gonadotropin, estradiol (E2), androgens, sex hormone-binding globulin (SHBG), and circulating mitotane levels were determined at diagnosis and during mitotane therapy. RESULTS: In the women included, ovarian macrocysts (bilateral in 51%) were detected after a median 11 months (range: 3-36) of mitotane exposure. The median number of macrocysts per woman was two (range: 1-4) and the median diameter of the largest cysts was 50 mm (range: 26-90). Menstrual irregularities and/or pelvic pain were present in 15 out of 21 women at macrocyst diagnosis. In two women, the macrocysts were revealed by complications (ovarian torsion and hemorrhagic macrocyst rupture) that required surgery. Mitotane therapy was associated with a significant decrease in androstenedione and testosterone levels and a significant increase in LH levels. Serum FSH and E2 levels were also increased, and SHBG levels rose markedly. CONCLUSIONS: Mitotane therapy causes significant morphological and ovarian/gonadotrope hormonal abnormalities in premenopausal women. Follicular thecal steroid synthesis appears to be specifically altered and the subsequent increase in gonadotropins might explain the development of macrocysts. The mechanisms underlying these adverse effects, whose exact prevalence in this population still needs to be determined, are discussed.


Asunto(s)
Carcinoma Corticosuprarrenal/sangre , Antineoplásicos Hormonales/uso terapéutico , Gonadotropinas/sangre , Mitotano/uso terapéutico , Quistes Ováricos/sangre , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/sangre , Premenopausia/sangre , Adolescente , Carcinoma Corticosuprarrenal/diagnóstico , Carcinoma Corticosuprarrenal/tratamiento farmacológico , Adulto , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/farmacología , Biomarcadores/sangre , Femenino , Humanos , Persona de Mediana Edad , Mitotano/efectos adversos , Mitotano/farmacología , Quistes Ováricos/inducido químicamente , Quistes Ováricos/diagnóstico , Ovario/efectos de los fármacos , Ovario/metabolismo , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/diagnóstico , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/tratamiento farmacológico , Premenopausia/efectos de los fármacos , Estudios Retrospectivos
7.
Chem Asian J ; 8(12): 2984-3001, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24019268

RESUMEN

A series of octupolar fluorophores built from a triphenylamine (TPA) core connected to electron-withdrawing (EW) peripheral groups through conjugated spacers has been synthesized. Their photoluminescence, solvatochromism, and two-photon absorption (2PA) properties were systematically investigated to derive structure-property relationships. All derivatives exhibit two 2PA bands in the 700-1000 nm region: a first band at low energy correlated with a core-to-periphery intramolecular charge transfer that leads to an intense 1PA in the blue-visible range, and a second more intense band at higher energy due to an efficient coupling of the branches through the TPA core. Increasing the strength of the EW end groups or the length of the conjugated spacers and replacing triple-bond linkers with double bonds induces both enhancement and broadening of the 2PA responses, thereby leading to cross-sections up to 2100 GM at peak and higher than 1000 GM over the whole 700-900 nm range. All derivatives exhibit intense photoluminescence (PL) in low- to medium-polarity environments (with quantum yields in the 0.5-0.9 range) and display a strong positive solvatochromic behavior (with Lippert-Mataga specific shifts ranging from 15,000 to 27,500 cm(-1)), triple bonds, and phenyl moieties in the conjugated spacers, thereby leading to larger sensitivities than those of double bonds and thienyl moieties. More hydrophilic derivatives were also shown to be biocompatible, to retain their 2PA and PL properties in biological conditions, and finally to be suitable as polarity sensors for multiphoton cell imaging.


Asunto(s)
Compuestos de Anilina/química , Colorantes Fluorescentes/química , Fotones , Compuestos de Anilina/síntesis química , Colorantes Fluorescentes/síntesis química , Células HEK293 , Humanos , Microscopía Fluorescente , Estructura Molecular , Relación Estructura-Actividad
8.
Chemistry ; 18(39): 12487-97, 2012 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-22907896

RESUMEN

Novel tripodal derivatives with a triphenylamine core and that bear "superacidifiers" (i.e., fluorinated sulfoximinyl blocks) or novel sulfiliminyl moieties as peripheral groups were synthesized. These new chromophores show strong absorption in the near-UV region and emission in the visible region. The fluorinated sulfoximinyl moieties were found to behave as potent auxochromic and electron-withdrawing (EW) groups, thus leading to redshifted absorption and emission. These moieties promote a core-to-periphery intramolecular charge transfer (ctp-ICT) transition, the energy of which was found to be correlated to their EW strength. In this study, we provide evidence of a linear correlation between the Hammett constant (σ(p)) values and the electronic gap between the ground and first excited state of the three-branched derivatives. This in turn was used to derive σ(p) values of fluorinated sulfoximinyl moieties. These EWGs show unprecedentedly high σ(p) values, up to 1.45 relative to 0.8 for NO(2). Also, by using this method, the sulfiliminyl moiety was shown to exhibit similar EW strength as NO(2) , while promoting improved transparency and solubility. Finally, the superior EW strength of the fluorinated sulfoximine peripheral moieties was shown to induce significant enhancement of the two-photon absorption responses in the red near-IR region of the three-branched derivatives relative to similar octupoles that bear more usual strong EW groups. These characteristics (improved nonlinear responses or transparency) open new routes for the design of nonlinear optical (NLO) chromophores for optical limiting or electro-optical modulation. Such building blocks could also be of interest for optoelectronic applications, including the development of solar cells.


Asunto(s)
Compuestos de Anilina/química , Hidrocarburos Fluorados/química , Compuestos de Terfenilo/química , Absorción , Electrones , Espectroscopía de Fotoelectrones
9.
J Clin Endocrinol Metab ; 96(9): 2796-804, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21752886

RESUMEN

CONTEXT: Mitotane is highly effective in the long-term management of Cushing's syndrome but has a slow onset of action. Mitotane combined with fast-acting steroidogenesis inhibitors might avoid the need for emergency bilateral adrenalectomy in patients with severe hypercortisolism. OBJECTIVE: Our objective was to assess the efficacy and safety of combination therapy with mitotane, metyrapone, and ketoconazole in severe ACTH-dependent Cushing's syndrome. PATIENTS, DESIGN, AND SETTING: Eleven patients with severe Cushing's syndrome participated in this follow-up study in a tertiary referral hospital. INTERVENTIONS: High-dose therapy combining mitotane (3.0-5.0 g/24 h), metyrapone (3.0-4.5 g/24 h), and ketoconazole (400-1200 mg/24 h) was initiated concomitantly. Twenty-four-hour urinary free cortisol (UFC) excretion (normal values 10-65 µg/24 h) was monitored. RESULTS: Data are reported as medians (range). All 11 patients experienced a marked clinical improvement. UFC excretion fell rapidly from 2737 µg/24 h (range 853-22,605) at baseline to 50 µg/24 h (range 18-298) (P = 0.001) within 24-48 h of treatment initiation and remained low to normal on the combination therapy. In seven patients, metyrapone and ketoconazole were discontinued after 3.5 months (range 3.0-6.0) of combination therapy, and UFC excretion remained controlled by mitotane monotherapy (UFC 17 µg/24 h, range 5-85; P = 0.016). Five patients became able to undergo etiological surgery and are presently in remission. Four of them recovered normal adrenal function after mitotane discontinuation. Adverse effects were tolerable, consisting mainly of gastrointestinal discomfort and a significant rise in total cholesterol and γ-glutamyl transferase levels (P = 0.012 and P = 0.002, respectively). CONCLUSIONS: When surgical treatment for severe ACTH-dependent Cushing's syndrome is not feasible, combination therapy with mitotane, metyrapone, and ketoconazole is an effective alternative to bilateral adrenalectomy, a procedure associated with significant morbidity and permanent hypoadrenalism.


Asunto(s)
Antimetabolitos/uso terapéutico , Antineoplásicos/uso terapéutico , Síndrome de Cushing/tratamiento farmacológico , Cetoconazol/uso terapéutico , Metirapona/uso terapéutico , Mitotano/uso terapéutico , Adolescente , Adulto , Anciano , Síndrome de Cushing/orina , Quimioterapia Combinada , Femenino , Humanos , Hidrocortisona/orina , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
10.
Chem Soc Rev ; 39(4): 1233-9, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20309483

RESUMEN

Fluorogenic Cu(I)-catalyzed alkyne-azide cycloaddition (CuAAC) reactions have emerged as a powerful tool for bioconjugation, materials science, organic synthesis and drug discovery. This review highlights the design of the recent development of fluorogenic CuAAC reactions as well as their applications.


Asunto(s)
Colorantes Fluorescentes/química , Alquinos/química , Azidas/química , Catálisis , Cobre/química , Ciclización , ADN/química , Nanopartículas/química , Polímeros/química , Virus/química
11.
J Phys Chem B ; 114(9): 3152-69, 2010 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-20163097

RESUMEN

The aim of the present work is to demonstrate that combined spatial tuning of fluorescence and two-photon absorption (TPA) properties of multipolar chromophores can be achieved by introduction of slight electronic chemical dissymmetry. In that perspective, two model series of structurally related chromophores have been designed and investigated. One is based on rod-like quadrupolar chromophores bearing either two identical or different electron-donating (D) end groups and the other on three-branched octupolar chromophores built from a trigonal donating moiety bearing identical or different acceptor (A) peripheral groups. The influence of the electronic dissymmetry is investigated by combined experimental and theoretical studies of the linear and nonlinear optical properties of dissymmetrical chromophores compared to their symmetrical counterparts. In both types of systems (i.e., quadrupoles and octupoles), experiments and theory reveal that excitation is essentially delocalized and that excitation involves synchronized charge redistribution (i.e., concerted intramolecular charge transfer) between the different D and A moieties within the multipolar structure. In contrast, the emission stems only from a particular dipolar subunit bearing the strongest D or A moiety due to fast excitation localization after excitation, prior to emission. Hence, control of emission characteristics (polarization and emission spectrum), can be achieved, in addition to localization, by controlled introduction of electronic dissymmetry (i.e., replacement of one of the D or A end-groups by a slightly stronger D' or A' unit). Interestingly, slight dissymmetrical functionalization of both quadrupolar and octupolar compounds does not lead to significant loss in TPA responses and can even be beneficial due to the spectral broadening and peak position tuning that it allows. This study thus reveals an original molecular engineering route allowing TPA enhancement in multipolar structures, due to concerted core-to-periphery or periphery-to-core intramolecular charge redistribution upon excitation, while providing for control of emission localization. Such a route could be extended to more intricate (dendritic) and multipolar (3D) systems.


Asunto(s)
Fotones , Compuestos de Terfenilo/química , Absorción , Fluorescencia , Conformación Molecular , Solventes/química , Compuestos de Terfenilo/síntesis química
12.
J Am Soc Mass Spectrom ; 21(3): 403-10, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20044271

RESUMEN

Cu(I) catalyzed alkyne-azide cycloaddition reaction was employed to synthesize a series of anthracene-based human thymidylate synthase (hTS) inhibitor analogues. The triazolo-anthracene derivatives were characterized by ESI-MS/MS and a novel rearrangement reaction in ESI-MS/MS was observed. The mechanism is proposed whereby the protonated triazolo-anthracene derivative forms a carbocation, and then the carbocation electrophilically attacks an anthracene moiety resulting in formation of a rearrangement ion. Moreover, the carbocation prefers to attack the gamma position rather than the alpha or beta position of the anthracene moiety by an electrophilic substitution mechanism.


Asunto(s)
Antracenos/química , Colorantes Fluorescentes/química , Modelos Químicos , Modelos Moleculares , Espectrometría de Masa por Ionización de Electrospray/métodos , Timidilato Sintasa/antagonistas & inhibidores , Antracenos/análisis , Humanos , Conformación Proteica
13.
Chemistry ; 15(1): 198-208, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19058267

RESUMEN

Two series of related donor-acceptor conjugated dipolar, pseudo-quadrupolar (V-shaped) and octupolar molecular systems based on the p-dimesitylborylphenylethynylaniline core, namely, 4-(4-dimesitylborylphenylethynyl)-N,N-dimethylaniline, 4-[4-(4-dimesitylborylphenylethynyl)phenylethynyl]-N,N-dimethylaniline, 3,6-bis(4-dimesitylborylphenylethynyl)-N-n-butylcarbazole and tris[4-(4-dimesitylborylphenylethynyl)phenyl]amine, and on the E-p-dimesitylborylethenylaniline motif, namely, E-4-dimesitylborylethenyl-N,N-di(4-tolyl)aniline, 3,6-bis(E-dimesitylborylethenyl)-N-n-butylcarbazole and tris(E-4-dimesitylborylethenylphenyl)amine have been synthesised by palladium-catalyzed cross-coupling and hydroboration routes, respectively. Their absorption and emission maxima, fluorescence lifetimes and quantum yields have been obtained and their two-photon absorption (TPA) spectra and TPA cross-sections have been examined. Of these systems, the octupolar compound tris(E-4-dimesitylborylethenylphenyl)amine has been shown to exhibit the largest TPA cross-section among the two series of approximately 1000 GM at 740 nm. Its TPA performance is comparable to those of other triphenylamine-based octupoles of similar size. The combination of such large TPA cross-sections and high emission quantum yields, up to 0.94, make these systems attractive for applications involving two-photon excited fluorescence (TPEF).

14.
Chemphyschem ; 8(5): 723-34, 2007 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-17295344

RESUMEN

The photophysical and linear and nonlinear spectral properties of octupolar compounds with a triphenylbenzene core are investigated and compared with properties of corresponding dipolar branches. A correlation is found between the solvatochromic behavior and the two-photon absorption cross section. Moreover, the nature of the core is found to be responsible for the nature of the coupling between branches; in the studied case only (weak) electrostatic interactions are effective, while other cores, like the triphenylamine moiety, are able to promote coherent coupling between the branches, leading to strongly nonadditive properties.

15.
Diabetes Care ; 29(7): 1619-25, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16801588

RESUMEN

OBJECTIVE: Early identification of subjects at high risk for diabetes is essential, and random HbA(1c) (A1C) may be more practical than fasting plasma glucose (FPG). The predictive value of A1C, in comparison to FPG, is evaluated for 6-year incident diabetes. RESEARCH DESIGN AND METHODS: From the French cohort study Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR), 1,383 men and 1,437 women, aged 30-65 years, were volunteers for a routine health check-up. Incident diabetes was defined by FPG >or=7.0 mmol/l or treatment by antidiabetic drugs. Multivariate logistic regression models were used to predict diabetes at 6 years. Receiver operating characteristic curves compared the predictive values of A1C and FPG. RESULTS: At 6 years, 30 women (2.1%) and 60 men (4.3%) had developed diabetes. Diabetes risk increased exponentially with A1C in both sexes (P < 0.001). After stratifying on FPG, A1C predicted diabetes only in subjects with impaired fasting glucose (IFG) (FPG >or=6.10 mmol/l): the odds ratio (95% CI) for a 1% increase in A1C was 7.20 (3.00-17.00). In these subjects, an A1C of 5.9% gave an optimal sensitivity of 64% and specificity of 77% to predict diabetes. CONCLUSIONS: A1C predicted diabetes, even though the diagnosis of diabetes was based on FPG, but it was less sensitive and specific than FPG. It could be used as a test if fasting blood sampling was not available or in association with FPG. In subjects with IFG, A1C is better than glucose to evaluate diabetes risk, and it could be used to select subjects for intensive early intervention.


Asunto(s)
Diabetes Mellitus Tipo 2/etiología , Hemoglobina Glucada/análisis , Adulto , Anciano , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/epidemiología , Progresión de la Enfermedad , Ayuno/sangre , Femenino , Francia/epidemiología , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y Especificidad
16.
Chem Commun (Camb) ; (22): 2802-4, 2005 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-15928763

RESUMEN

New fluorophores, combining broad, very high two-photon absorption in the near-infrared region with a marked dependence of their emission spectra on solvent polarity, have been designed as model probes for two-photon sensing of the chemical environment.


Asunto(s)
Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/química , Sondas Moleculares/análisis , Sondas Moleculares/química , Fotones , Estructura Molecular , Fotoquímica , Solventes , Tolueno/química
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