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1.
Article in English | MEDLINE | ID: mdl-38668766

ABSTRACT

Negative symptoms in CHR-P people are generally not responsive to treatments and commonly related to poorer functional outcome. However, less research attention has been dedicated to Persistent Negative Symptoms (PNS), defined as clinically stable negative symptoms of moderate severity evident for at least 6 months. This study aims to (a) determine the prevalence of PNS in a sample of young people at CHR-P; (b) investigate any association of PNS with functioning and clinical features; (c) examine longitudinal course of PNS across 2 years of follow-up and changes in PNS severity levels with specialized treatments. One Hundred Eighty CHR-P participants were recruited and were divided into CHR-P/PNS + and CHR-P/PNS- subgroups. The clinical assessments were based on the PANSS and the GAF and were conducted at baseline and every 12 months during the follow-up. Twenty four participants showed PNS at entry. Of them, 21 concluded the 2-year follow-up period. At baseline, the CHR-P/PNS + participants showed more educational and employment deficits, and more social and functioning impairment. During the follow-up, the CHR-P/PNS + subgroup had a significant longitudinal decrease in negative symptoms, which was specifically related to antidepressant treatment. CHR-P/PNS + subjects also showed a higher incidence of new hospitalization and a lower functional recovery over time. Our findings support that the persistence of negative symptoms in CHR-P people is longitudinally related to worse daily functioning and more severe clinical conditions that are at higher risk of hospitalization and are less responsive to specialized treatments.

2.
Anal Chim Acta ; 623(2): 178-86, 2008 Aug 15.
Article in English | MEDLINE | ID: mdl-18620922

ABSTRACT

Pharmaceutical counterfeiting has become a significant public health problem worldwide and new, rapid, user-friendly, reliable and inexpensive methods for drug quality screening are needed. This work illustrates the chemical characterization of genuine and fake artesunate antimalarial tablets by portable Raman spectroscopy and validation by FT-Raman spectroscopy and ambient mass spectrometry. The applicability of a compact and robust portable Raman spectrometer (TruScan) for the in situ chemical identification of counterfeit tablets is reported.


Subject(s)
Antimalarials/analysis , Artemisinins/analysis , Fourier Analysis , Fraud , Mass Spectrometry/methods , Spectrum Analysis, Raman/instrumentation , Artesunate , Quality Control , Reproducibility of Results , Tablets
3.
Anal Bioanal Chem ; 392(1-2): 37-45, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18437366

ABSTRACT

The potential of attenuated total reflection Fourier transform infrared (ATR-FTIR) imaging for the characterisation of the chemical components of paint cross sections from old master paintings was investigated. Three cross sections were chosen to cover a variety of the analytical problems encountered in samples from paintings. The binding medium and degradation products in a green paint sample from a fifteenth-century Florentine painting were imaged, as well as a thin layer within a cross-section from a fifteenth-century German painting, and multiple thin surface coatings on a painting of the 1760s by Peter Romney. The application of chemometric methods for further analysis of the large data set generated for each sample was also explored. The study demonstrated the advantages of ATR-FTIR imaging, which allowed images to be obtained with high spatial resolution (ca. 3-4 microm) without the need to microtome the sample. The gain in sensitivity in detecting trace materials and the information derived from the location of these compounds in the sample was especially valuable, improving interpretation of the FTIR analysis and extending knowledge of the sample composition beyond that obtainable with other analytical techniques.

4.
Anal Bioanal Chem ; 389(5): 1525-32, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17879090

ABSTRACT

In support of the efforts to combat the illegal sale and distribution of counterfeit anti-malarial drugs, we evaluated a new analytical approach for the characterization and fast screening of fake and genuine artesunate tablets using a combination of Raman spectroscopy, Spatially Offset Raman Spectroscopy (SORS) and Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) imaging. Vibrational spectroscopy provided chemically specific information on the composition of the tablets; the complementary nature of Raman scattering and FTIR imaging allowed the characterization of both the overall and surface composition of the tablets. The depth-resolving power of the SORS approach provided chemically specific information on the overall composition of the tablets, non-invasively, through a variety of packaging types. Spatial imaging of the tablet surface (using ATR-FTIR) identified the location of domains of excipients and active ingredients with high sensitivity and enhanced spatial resolution. The advantages provided by a combination of SORS and ATR-FTIR imaging in this context confirm its potential for inclusion in the analytical protocol for forensic investigation of counterfeit medicines.


Subject(s)
Artemisinins/analysis , Sesquiterpenes/analysis , Spectroscopy, Fourier Transform Infrared/methods , Spectrum Analysis, Raman/methods , Tablets/analysis , Antimalarials/analysis , Artesunate
5.
Anal Chem ; 79(15): 5771-6, 2007 Aug 01.
Article in English | MEDLINE | ID: mdl-17602672

ABSTRACT

This work introduces a new and nondestructive methodology for the collection and chemical identification of latent fingermarks. The main challenges of this work were (a) to find an appropriate medium to lift fingermarks from various surfaces and (b) to develop an analytical approach for the identification of small quantities of sample while avoiding spectroscopic interference from the lifting media. Two different lifting media were evaluated and analyzed by ATR-FT-IR spectroscopic imaging, which affords inherent chemical specificity with rapid acquisition of data. This is the first time that chemical images of latent fingermarks collected with gel lifters from different surfaces have been obtained. Spatially resolved chemical images from different depths within the same sample were obtained using ATR-FT-IR imaging with a variable angle ATR accessory to minimize interference from the substrate. The possibility of obtaining, through the developed methodology, three-dimensional depth profiles of surface contaminants collected with the lifting gel shows great potential for the investigation of samples for forensic interest.

6.
Appl Spectrosc ; 61(5): 514-22, 2007 May.
Article in English | MEDLINE | ID: mdl-17555621

ABSTRACT

In situ attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopic imaging has been used to obtain chemical images of fingerprints under controlled humidity and temperature. The distribution of lipid and amino acid components in the fingerprints from different donors left on the surface of the ZnSe crystal has been studied using an in situ FT-IR spectroscopic imaging approach under a controlled environment and studied as a function of time. Univariate and multivariate analyses were employed to analyze the spectroscopic dataset. Changes in the spectra of lipids with temperature and time have been detected. This information is needed to understand aging of the fingerprints. The ATR-FT-IR spectroscopic imaging offers a new and complementary means for studying the chemistry of fingerprints that are left pristine for further analysis. This study demonstrates the potential for visualizing the chemical changes of fingerprints for forensic applications by spectroscopic imaging.


Subject(s)
Fingers , Skin/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Sweat/chemistry , Adult , Dermatoglyphics , Female , Humans , Male
7.
Anal Bioanal Chem ; 387(2): 551-9, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17136340

ABSTRACT

This paper reports use of a combination of Fourier-transform infrared (FTIR) spectroscopic imaging and desorption electrospray ionization linear ion-trap mass spectrometry (DESI MS) for characterization of counterfeit pharmaceutical tablets. The counterfeit artesunate antimalarial tablets were analyzed by both techniques. The results obtained revealed the ability of FTIR imaging in non-destructive micro-attenuated total reflection (ATR) mode to detect the distribution of all components in the tablet, the identities of which were confirmed by DESI MS. Chemical images of the tablets were obtained with high spatial resolution. The FTIR spectroscopic imaging method affords inherent chemical specificity with rapid acquisition of data. DESI MS enables high-sensitivity detection of trace organic compounds. Combination of these two orthogonal surface-characterization methods has great potential for detection and analysis of counterfeit tablets in the open air and without sample preparation.


Subject(s)
Antimalarials/analysis , Drug Contamination , Antimalarials/standards , Artemisinins/analysis , Artesunate , Diagnostic Imaging , Quality Control , Sesquiterpenes/analysis , Spectrometry, Mass, Electrospray Ionization/methods , Spectroscopy, Fourier Transform Infrared/methods , Tablets/analysis
8.
Appl Spectrosc ; 60(9): 1013-21, 2006 Sep.
Article in English | MEDLINE | ID: mdl-17002827

ABSTRACT

Conventional Fourier transform infrared (FT-IR) spectroscopy and microscopy have been widely used in forensic science. New opportunities exist to obtain chemical images and to enhance the spatial resolution using attenuated total reflection (ATR) FT-IR spectroscopy coupled with a focal-plane array (FPA) detector. In this paper, the sensitivity limits of FT-IR imaging using three different ATR crystals (Ge, ZnSe, and diamond) in three different optical arrangements for the detection of model particles is discussed. Model systems of ibuprofen and paracetamol particles having sizes below 32 mum were studied. The collection of drug particles was achieved with the aid of two different tapes: common adhesive tape and a film of polydimethylsiloxane (PDMS). The surface of the film with collected particles was measured directly via ATR-FT-IR imaging. Since the removal of tape from porous surfaces can be difficult, the application of micro ATR-FT-IR imaging directly to the surface of a newspaper contaminated with particles of model drugs is also discussed. In order to assess the feasibility of the chosen method in a forensic case study, the detection of diacetylmorphine hydrochloride traces in PDMS matrix and the finger surface is investigated. The scenarios considered were that of the detection of evidence collected at a crime scene with the tape lift method and the analysis of the finger of an individual after drug handling. The results show broad implications in the detection of drugs of abuse.


Subject(s)
Heroin/analysis , Spectroscopy, Fourier Transform Infrared/methods , Substance Abuse Detection/methods , Acetaminophen/analysis , Alloys , Diamond , Dimethylpolysiloxanes , Fingers , Forensic Sciences , Germanium , Humans , Ibuprofen/analysis , Particle Size , Porosity , Selenium , Silicones , Spectroscopy, Fourier Transform Infrared/instrumentation , Zinc
9.
Talanta ; 69(5): 1221-6, 2006 Jul 15.
Article in English | MEDLINE | ID: mdl-18970706

ABSTRACT

Research work using a compact and portable fiber optic mid-infrared reflectance spectrometer has been carried out to study surface materials on marble, first on laboratory reference models and then on historical objects. The laboratory research has shown that the complex optical reflectance phenomena of layered samples can be interpreted in terms of the nature of the compounds present (sulfates, oxalates, phosphates, resins, waxes and proteins were studied) even with a very low signal overlapping with the strong carbonate reflectance. The portable instrument was used for in situ examination of the surface condition of two Italian marble works of art: the Deposizione dalla Croce by Benedetto Antelami in the Parma cathedral and the David by Michelangelo in the Galleria dell'Accademia in Firenze.

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